j s tBJOptica i 
CHARLES STODDER, 
RIALTO, Room 36, 
131 Devonshire, Corner of Milk Street. ' 
IMPORTER, 
AND AGENT FOR W. WALES' AND JOS. ZENTMAYKR'S 
MICROSCOPES. 
SOLE AGENT FOR THE SALK OF 
MICROSCOPES and TELESCOPES | 
made by 
R. B. TOLLES. 
Goi.n Medal of the Marr, viiaritahle Mechanic Association, 1869. 
Silver medal of the exposition universelle, paris, 1867. 
15th EDITION. PRICE 15 CENTS. 
BOSTON: 
ALFRED MUDGE & SON, PRINTERS, 34 SCHOOL STREET. 
1879. A WORD TO PURCHASERS OF MIC 
Although magnifying-glasses have been used for time imme- 
morial, and valuable discoveries were made by them centuries 
ago, yet it is only within the last fifty years, when the method 
of constructing achromatic lenses was discovered, that the 
microscope began to be an instrument of real scientific value. 
Since that time, from the united labors of skilful opticians and 
accomplished scientists, there has been a continual series of 
improvements and new inventions of apparatus, the end of 
which is not yet. 
Of all instruments of scientific research, there is no one which 
requires greater skill in its construction, and no one of which 
there is such an almost endless variety of forms, shapes, and 
quality, of both the optical and mechanical construction. Ou 
the continent of Europe great advance in construction had been 
made by eminent opticians; but it is not too much to say that 
nearly all the really valuable improvements made during the 
last five decades, in the form of the instrument, and in the 
quality of the optical parts, have originated either in England 
or America, and that the best work of many of the continental 
opticians, who yet have a good reputation there, is twenty years 
behind the times, while they still continue to produce quantities 
of instruments that are absolutely worthless, except as toys. 
There are certain qualities absolutely necessary to a micro- 
scope, if it is to be any other than a plaything, which every 
purchaser should see that his instrument possesses. First, the 
optical part, the lenses, should be at least of good quality. The 
all-important requisition is good definition, freedom from color 
and flatness of field included. There are various qualities iu 
lenses; some are adapted best for one class of studies, some 
for another. No novice can judge of the performance of a 
microscope; it requires long experience.* 
Secondly, the mechanical work must be simple, of the fewest 
possible number of pieces, not liable to get out of order. The 
stand must be well made, or it will not keep in working condi- 
tion, but require frequent repair. It must be heavy enough to 
stand firmly, not easily moved or upset. Not less than five to 
six pounds weight is efficient. Fifteen pounds is desirable. 
• For the qualities to be looked for in a first-claw objective, see quotation from 
Dr. Richardson, p. 12. 2 
,e distance of distinct vision is about ten inches, 
\ adopted as the standard length; t. e. the dis- 
tance . the eye and the object, or more exactly, between 
the optical centre of the objective, and the optical centre of the 
eye-piece : many cheap instruments have tubes of only four or 
five inches; as a length of ten inches magnifies twice as much 
as one of five inches does, all that increase of power is lost 
by a short tube. The instrument should be made so as to 
admit of inclination at any angle, from vertical to horizontal. 
The best position for the microscope is such that the observer 
may sit at his ease in a chair, at a table. The vertical position 
of the tube is "the very worst that can be adopted."- Car- 
penter. 
Many novices think that the value of a microscope depends 
on how much it will magnify. This is a great error; the most 
worthless instrument may magnify highly. More can be seen 
with a good instrument with a power of one hundred diameters 
than with a poor one of five hundred. 
Every microscope consists of two essential divisions, - in 
a sense independent of each other, - though either is useless 
alone; viz. the mechanical part, or stand, and the optical 
parts, or lenses. One of these parts may be good, and the 
other inferior. The optical part consists of the objective and 
eye-piece. Each instrument may be furnished by the maker 
with any number and power of objectives and eye-pieces that 
the purchaser requires for his special use, or is willing to pay 
for. 
Finally, every beginner should have a standard recent book on 
the microscope, or he will have to feel his way blindly over 
roads that have been already travelled. What would be thought 
of a man who should attempt to make a watch who did not first 
ascertain how watches have been made? With "Carpenter" or 
"Hogg" in his hands, the novice may learn in a short time 
what it might take him years to discover by his own unaided 
efforts.* It is more economical to purchase an instruction book 
than to pay a teacher, not meaning, however, that a good in- 
structor is not desirable. 
As there is want of information as to the meaning of the 
magnifying power of lenses, some explanation of the principles 
will be of service. 
The " power " of a lens is not a fixed mathematical fact, but 
the power is calculated from an arbitrary standard; i. e. what 
a lens would magnify an object ten inches from the eye, if 
natural vision was just ten inches. Any change of this dis- 
tance will change the nominal power. Objectives and eye- 
" How to Use the Microscope," by John Phin, can be recommended to beginners as 
the best book at a low price. 3 
pieces being made up of combinations of lenses, th' 
as they magnify equal to a single lens ; that is, if <* 
of lenses magnifies the same as a single lens of one inch focus it 
is called a one-inch ; if the same as single lens of a quarter-inch 
focus, then it is a "quarter-inch," and so for all others. 
Now a one-inch lens, or objective, is said to magnify an object 
ten diameters, if the object is ten inches distant, and a -X will 
magnify 100 diameters. The number of times the focal length 
is contained in ten inches is the power; but the image formed 
in the microscope by the objective is again magnified by the 
eye-piece, consequently, the power of the objective must be 
multiplied by the power of the eye-piece. Thus a objec- 
tive power 100 X by one-inch eye-piece 10 = 1,000 diameters. 
With the new nomenclature of eye-pieces, every owner can 
calculate the theoretical power of his own instrument. If the 
distance between the optical centre of the objective and the 
optical centre of the eye-piece varies from ten inches, the 
resulting power will vary in proportion. 
TOLLES'S STUDENT'S MICROSCOPE. 
15 INCHES HIGH, WEIGHT SIX POUNDS. 
This instrument, designed under the advice of several of the 
Professors of the Medical School of Harvard College and other 
well-known Microscopists, is of the pattern and size most ap- 
proved by experts. The base, uprights, and curved arm are of 
iron, handsomely japanned ; on a trunnion joint, made on a new 
plan to wear well, by which the instrument can be placed in 
any position, from vertical to horizontal, with a stop to prevent 
movement in either direction beyond these points. It is fur- 
nished with a 1-inch Eye-Piece, two second-quality Objectives, 
of about 1 inch and 1-4 inch power, giving about 80 and 350 
diameters, a plain Stage with spring clips for holding the object 
slides, revolving Diaphragm, concave Mirror, with movement 
to give oblique light; for illumination of opaque objects, the 
mirror is removed to an upright stand; coarse adjustment for 
focus is effected by sliding the compound body which is held 
in its place by a spring, fine adjustment by a movable plate and 
screw on the stage, which is efficient with high powers. The 
stand is made with all the care bestowed on his first-class instru- 
ments, and proves satisfactory for the use of amateurs, students, 
and the ordinary work of the medical profession. The work- 4 
iperior to that of any instruments of the class made 
.. ......ope. The form is the Jackson pattern recommended by 
Dr. W. B. Carpenter as the one least liable to tremor, and is 
the one most approved by all American microscopists. Price, 
in an upright Black Walnut Case, $50. Stand and Case alone $28. 
Variations and Additions. - Extra Eye-Pieces, 2 in. 1 1-2 
and 3-4, $4 each ; a superior Camera Lucida, $5 : Sub-Stage for 
accessory apparatus, $5 ; a Sliding Stage, giving vertical and hor- 
izontal motions by the hand, and adapted for the use of Maltwood 
tinder, $15. Fine adjustment by lever and micrometer screw, 
$20. Rack and Pinion lor coarse adjustment, $12, draw tube, $4. 
Plain Mirror, $3. Thin glass stage to rotate on the optical 
axis, $10. The stand all brass, $10. Any of Tolles's first 
quality Objectives may be used on this instrument, and can 
be added to order at list prices. Packing boxes for transporta- 
tion, $1. 
Student's Microscope, with 1- 
inch and fin. Objectives, one 
ocular, rack and pinion, lever 
fine adjustment for focus, sub- 
stage for illuminating appara- 
tus, revolving diaphragm, plain 
and concave mirrors, side-stand 
for illuminating opague objects, 
-black walnut case. Price, $90. 
TOLLES'S STUDENT'S MICROSCOPE. 
From Dr. Geo. E. Blackiiam, President Dunkirk Microscope Society. 
August, 1875. 
Mr. Chas. Stodder : 
Dear Sir, - As to the Student's Stand, I am simply delighted with 
it. It is remarkably steady on its feet, and shows no inclination to 
kick up its heels when the body is placed horizontal for drawing. 
This cannot be said of many higher-priced stands that I know of. 
2d. The Jackson model and full length of tube meet my hearty 5 
approval. Wenham's new model Ross stand is about the clu»>r 
looking affair 1 ever saw. 3d. The arrangement for control*, 
movement of the sliding tube is the only one in which I have ever been 
able to take any comfort. Proof: I used my duplex |th on this stand, 
and I would not risk it on any other sliding-tube stand I have ever 
tried so far. As to its superiority over the rack and pinion, that de- 
pends. That it is better than a poor or even moderately good rack 
and pinion, there can be no doubt. I can do just as good work with 
this, but it is a little more trouble. 4th. The fine adjustment is emi- 
nently satisfactory, though 1 have been much prejudiced against line 
adjustment moving the stage. 5th. The joint for inclination works 
with a perfection unsurpassed by any first-class stand I ever saw, and 
appears to be a triumph of mechanical simplicity. 
As to the objectives, I was pleasantly surprised at their excellence ; 
I knew of course that Tolles never sent out any work that was not good, 
but had no idea that these low-priced lenses were so good. Compared 
the J last night with a | furnished with . . . "physician's micro- 
scope " bought for the schools here at S90, and the superiority of the 
f was very marked. The object was a cluster of living vorticella, a 
legitimate natural-history application - no diatom. The f defined 
and showed the cillae, and the § did not. The too, is a fine lens, 
and excited considerable admiration by the clearness and sharpness of 
images. The one-inch is also remarkably good ; and in fact I should 
be inclined to rate all these objectives as first-class, had not my expe- 
rience with Tolles's £th and one-inch of 30° taught me what real first- 
class work is. 
The camera, too, is excellent: altogether, I am delighted with the 
outfit. 
THE POCKET MICROSCOPE 
For clinical and- field or seaside use is a simple tube 6 
inches long, with a one-quarter inch Objective and B Eye- 
Piece, - fine and coarse adjustments for focus, - a Stage with 
spring-clips to hold the object, which can be removed when not 
in use, and the Objective covered with a brass cap, making the 
most compact and efficient portable instrument in use. Price, 
$25 ; with a draw-tube for increasing the power, $29. As the 
same Eye-Pieces and Objectives are used for the Student's 
Microscope, those who want both instruments require but one 
set of the optical parts. All the other Objectives on the list 
can be used with both instruments, and can be supplied to order. 
The Objectives and Eye-Pieces supplied to these instruments 
are in all respects equal to those sent to this country, with many 
so-called first-class instruments from Berlin, and with those 
from many of the well-known opticians of Paris and London. 6 
THE PROFESSOR'S MICROSCOPE. 
This is an instrument similar to the clinical. It is intended 
to pass around a class of students. Is provided with a means 
of clamping the object slide to the stage, so that the particular 
object the lecturer is explaining cannot be moved out of the 
field, while each observer can adjust the focus to his own eye. 
Price without objectives, $25. This instrument and the 
"Pocket" are used without a stand by holding it in the hand 
and looking at the light. 
TOLLES'S LARGE MICROSCOPE. 
B. 
This instrument is intended to meet the wants of the highest 
scientific investigation ; to attain everything that the microscopist 
can accomplish, without 
k sparing the cost, and to 
permit the use of all the 
modern accessory appa- 
ratus. Like all of Tolles's 
microscopes, it is con- 
structed on the curved arm 
(Jackson) model, which 
Dr. W. B. Carpenter, in his 
elaborate work on " The 
Microscope," fourth edition, 
1868, preferred over all 
other models ; and in 1870, 
at a meeting of the Royal 
Microscopical Society, of 
London, still more em- 
phatically approved in a 
special communication, giv- 
ing his reasons for thus in- 
dorsing it. The instrument 
is eighteen inches high, 
weighs about fourteen lbs., 
thus giving a stability and 
freedom from tremor that 
cannot be obtained with 
stands of little weight. It is of simple construction, with 
fewer screws and pieces than any other first-class micro- 7 
scope. The curved arm is supported on a steel trunnion 
between two strong brass pillars, made for durability, and not 
liable to get out of order, and provided with a method of 
compensation for wear. Has rack and pinion for coarse, and 
micrometer screw for fine adjustment for focus ; graduated draw 
tube; sub-stage with rack and pinion, and centring screws for 
accessory apparatus ; plain and concave mirrors, on double- 
jointed arm, Toiles's thin stage, admitting light of great ob- 
liquity, with rectangular movements by screw and rack and 
pinion, and rotation on the optical axis of about 325°, - all that 
is essentially necessary. Price, $225. 
A modification of this size, with the stage carried by friction 
rollers and entire rotation on the optical axis, can be made at 
an advanced price. 
TOLLES'S LARGEST MICROSCOPE. 
This instrument is one of the largest yet produced anywhere. 
It is similar in all respects of style and construction to the B 
instrument, but larger and heavier, weighing 20 lbs. The 
stage is six inches in diameter, and makes a complete revolution 
on the optical axis. The whole instrument rotates on a stout 
plate graduated to degrees. Price of Stand, $300. Can be 
furnished with radial arm, which describes a curve, of which 
the focal point is the centre, to carry accessory apparatus at any 
angle. A graduated arc registers the obliquity of the incident' 
light. This method of reading the angle of incident light and 
angular aperture was devised more than seven years ago. Other 
models of stands are now made. 
TOLLES'S LARGE STAND C, Price, $160. 
This stand has Toiles's patent radial arm, which carries the 
illumination above the stage, and measures the angle of inci- 
dence of the light. Toiles's patent traverse lens for utilizing 
balsam angles beyond 82° can be added to order on all the large 
or small stands. 8 
Dunkirk, N. Y., Dec. 3, 1878. 
As to the stand, T am more than pleased, -I am delighted. It is 
much handsomer to look at than I expected, and the workmanship is, 
as far as I can see, absolutely perfect. Such a rack and pinion and 
such a fine adjustment I have never seen elsewhere. The stage is 
about perfect. Finally let me thank you most heartily and sincerely 
for having made this exquisite instrument for me and for the time, 
skill, and genius you have expended on the construction. So far as I 
can now judge, it more than fills my highest expectations, and is, I 
believe, the best microscope yet made. 
GEO. E. BLACKHAM, M. D., 
President Dunkirk Microscopical Society. 9 
PRICES OF TOLLES'S INSTRUMENTS. 
SOLD BY CHARLES STODDER. 
Huyghen's Negative Eye-Piece, 2 in., 1 1-2 in., 1 in., 3-4 in., $8 each. 
" " " " for Student's Microscopes, $4 each. 
Tolles's Patent Solid Eye-Pieces, 1-2 in., 1-4 in., 3-8 in., $8; 1-8 in., $12. 
" " " " " for Student's Microscopes, $6. 
( Tolles's Solid Orthoscopic Eye-Pieces, 1 in., $15, higher powers, $12. 
| This Eye-Piece makes an excellent achromatic condenser. 
Tolles's Binocular Eye-Piece, $80. See pp. 17, 18. 
Tolles's Amplifier, to double the power of any specified Objective and Eye- 
Piece without disturbing the " corrections," $12. 
Higher power amplifiers of another construction by special arrangement. 
Tolles's Achromatic Triplets for the pocket, in Silver cases, 1-2 in. ard 3-4 in., 
$12; 3-4 in., extra large mounting, $14; 1-4 in., $14. 
1-in. do., do., with 6-10 in. field, $16. 
Double Nose-Piece, $8 to $16. Angular Double Nose-Piece, $12. 
Camera Lucida, $5. 
Tolles's Improved Telescopes, 
1 in. lens, 5 in. focus, on stand do. with pancratic Eye-Piece, $70. 
2 1-2 in. lens, 22 to 27 in. focus, on iron tripod, $175 to $250. See pp. 19, 20. 
2 1-2 in. do. on Engineer's tripod, $150. 
4 in. do. on iron tripod, $300. 
Telescopes of any Aperture, of unusually short focal length, made under 
special contract. 
Wenham's Reflex Illuminator, $10. 
TOLLES makes four classes of microscope objectives, viz.: - 
FIRST QUALITY OF LARGE ANGULAR APERTURE. These are made 
for the highest requirements of the microscopist and histologist, as tracing nerve 
fibre, cell formation, resolution of Nobert's lines, etc., etc. 
1-2 inch ang. ap. 60° to 80° $40 
4-10 " " 90° to 120° 45 
( 4-10 " " 135° to 145° 65 
( This objective may be used as an achromatic condenser, with special advantage. 
1-4 inch or 1-5 ang. ap. 120° to 130° $45 
1-4 " " " up to 150° 55 
1-4 " " " " 180° 70 
1-6 " $5 advance on 1-4. 180° 70 
1-8 " ang. ap. to 160° 70 
1-8 " " to 180° 80 
1-10 " $5 advance on 1-8. 180° 85 
1-12 " ang. ap. under 140° 80 
1-12 " " up to 160° 90 
1-12 " " " to 180° 110 
1-15 " " " to 160° . . 110 
1-15 " " " to 180° 120 
1-20 " " " to 180° 150 
1-25 " " « to 180° 175 
1-50 " " by special contract. 
1-75 " " " " 
All objectives of 180° may be duplex front, or three systems, at option. 
These duplex or four system lenses have been made since 1871-3, marking the 
period of the great advance in the construction of objectives by utilizing the extra 
limit aperture beyond 82°. 
FIRST QUALITY OBJECTIVES having less angular aperture, more penetra- 
tion with first-class adjustment for cover. 
1-2 inch ang. ap. 60° or less , $35 
4-10 " " 85° " 40 
1- and 1-5 " " 100° to 120° 40 
1-6 " " 100° to 120° 45 
1-8 " " 100° to 130° 45 
1-10 " " 100° to 135° 50 
1-12 " "120° 55 
1-15 " "120° 60 
1-20 " " 140° . . . 80 
All of 1-4 inch or higher powers will be made either dry or immersion at the same 
price, or to work both ways with the same lens. With an extra " front " lens $10 to 
2- extra. All the foregoing have Toiles's adjustment for covering glass, which 
does not move the front lens, and has no back lash. 
MICROSCOPE OBJECTIVES. 10 
FIRST QUALITY OBJECTIVES, without adjustment for cover. 
4 inch adjustable to 3 inch $35 
2 inch 20 
2 inch higher ang. ap 23 
1 1-2 inch and 1 inch in one 25 
1 inch 14° 10 
1 inch 25° 23 
1 inch 30° 30 t 
3-4 inch new formula specially flat field 30 
1 2 inch 25° to 40° 23 
* 1-2 inch specially constructed for viewing opaque objects 1 * „„ r 
1-4 inch 40° to 70° adjusting by front lens do. do. j . . z r~ 
FIRST QUALITY IMMERSION OBJECTIVES, for oil of cedar wood or gly- \ 
cerine, requiring no adjustment for cover-glass. i 
1-6, 1-8, or 1-10 in. focus, 180° or more than 82° balsam . . . $40 / 
These objectives guaranteed to resolve amphipieura pellucida in balsam by lamp- ) 
light. 
SECOND QUALITY OBJECTIVES, without adjustment for cover. 
1-8 inch immersion 120° $25 
1-10 inch immersion 120° 30 
1-6 inch 90° to 100° 18 
1-4 inch or 1-5 inch 70° to 90° 15 
Will resolve well Pl. angulation. 
1-4 inch 40° to 50° 12 
Has a long working distance for opaque objects. 
1-2 inch 12 
2 inch and 1 1-2 inch 8 
1 inch 6 
All objectives are made with the " Society" screw, so as to fit all recent English 
or American stands, unless ordered otherwise. 
But few microscopists need references in regard to Mr. 
Toiles's optical instruments. But as there are yet some people 
who think it is necessary to go or send to Europe for good 
instruments, a few letters from those who know what good 
instruments are, are inserted, for their information. The sell- 
ing agent prefers to let purchasers see what is said by those 
who use Toiles's microscopes, rather than to make claims for 
superiority himself. 
From Henry Sharp, Green Hills, New South Wales, July 13,1879. 
Mb. C. Stodder, - So far as I have yet tested the Tolles 1-ldth objective I am 
more than satisfied with it, and have much pleasure in saying that I consider it by 
far the finest objective I have yet seen, and I neither expect or hope ever to see a 
better. It is truly a grand objective. Please convey to Mr. Tolles my best thanks 
for the care he has taken in its construction. I remarked that the prices of Mr. 
Toiles's lenses were high. I beg now to correct that, and I say that they are 
apparently high, but in reality are not so, as I consider this l-10th I have to be the 
cheapest objective I have ever bought. 
From Prof. Bessey, Iowa State Agricultural College, Ames, Jan. 9, 1871. 
The instrument (Toiles's Student's) is just what I want. I have tested it as much 
as my limited time would permit, and can assure you that so far it is perfectly satis- 
factory; I regard it as just the microscope for class use. 
Very respectfully, 
CHAS. E. BESSEY. 
From IF. H. Walmsley, Philadelphia, December, 1870. 
You ask my 'opinion of the objective (three quarter inch); it is simply glorious. 
Museum of Comparative Zoology, Cambridge, Mass., January, 1871. 
I have no hesitation in saying that Mr. Toiles's first-class microscope objectives (I 
have used and examined critically a great many of them) are the best I have seen, 
either of American or foreign make. The large microscope stand now being finished 
is, in my opinion, the best first-class stand made, and it meets more of the require- 
ments that are called for in a first-class instrument than any other that I have seen. 
The stage being roomy, extremely thin, very firm, and making an entire revolution 
* This is a new construction of a conical front lens, by the use of which a beam of 
light may be thrown directly on the object, permitting the use of higher powers and 
larger angular aperture than heretofore. 11 
on the optical axis, having the milled heads of the stage movements at the side, with 
nothing to interfere with the utmost obliquity of illumination, makes it the best stage in 
existence. In all first-class microscopes that 1 have heretofore seen, there has been 
one or more of the above requirements wanting. No one who wants a strictly first- 
class stand can do better than to procure the above. 
I have a one-inch telescope of Mr. Tolles's make of four inches focus, 15° ang. ap., 
which I have used on terrestrial objects with from 16 to 30 diameters, with fine effect; 
and I have used it with 25, 50 and 100 diameters on celestial objects with fine effect 
also. All of Mr. Tolles's larger telescopes that I have seen, have been equally good. 
Very truly yours, 
EDWIN BICKNELL. 
From letters from the late Dr. Th. Eulenstien, formerly of Dresden, lately of Berlin, 
N. Germany. 
Dresden, July 15,1868. 
" Mr. Green has delivered to me the one-sixth immersion. I can pronounce it one 
of the finest objectives I have seen for definition, richness, and blackness of the 
images. I shall expect your statement whether the highest powers now made by 
Tolles progressively excel the corresponding powers of other makers, same as his one- 
sixth certainly excels any lens of that power I have yet seen." 
Dresden, Feby. 11th, 1870. 
" I have sent the Tolles's 1-6 objective to Nobert, and he has closely examined it. 
We have both seen the lines of the 17th band of his test-plate; no more at present. 
This, however, is an extraordinary feat for a sixth; and more than any other lens 
that I know of, of that power, can possibly be stretched to do. I am sorry I cannot 
see one of Tolles's highest powers to enter into a comparative list I am preparing." 
TH. EULENSTIEN. 
This objective is now owned by Prof. Van Huerck, of Anvers, Belgium, who in 
December, 1876, calls it "admirable." 
Within a few years, very low power objectives have re- 
ceived much attention in London ; and a great many four (4) 
inch objectives have been made, and used with satisfactory 
results. A difficulty in the use of them arises from the long 
working distance which prevents their attachment to all micro- 
scopes. Mr. Tolles has recently constructed an objective which 
is either 3 or 4 inch at user's option; and with a working 
distance of one and three-quarters of an inch only, which can 
be reduced to one inch if so ordered. 
The following, from a well-known microscopist, corresponds 
with the opinion of all other experts who have seen the instru- 
ment. 
Philadelphia, March 19,1870. 
"I have had but a few moments to devote to the 4-inch lens, but those few enable 
me to say emphatically, that it is the best low power I ever saw and is far superior 
to Ross's 4 inch. The latter I have used very much, and liked, but found it to 
possess very considerable spherical aberration which is entirely corrected in Tolles's 
objective. 
" I shall keep it, most decidedly, and sell my Ross. I hope you will send one to 
London without delay." "Had it no other superiority, its short working distance 
would give it the preference; altogether, I am delighted with it. Ross's is a triplet, 
and also a single combination. The whole length is 11-16 of an inch; while its ex- 
treme diameter is 1 1-16 inch; giving it a very awkward look. The actual aperture 12 
of the front is 1-8 of an inch greater than Tolles's. The size of the field and magni- 
fying power of the two are precisely the same. Fields equally ill iminated, bnt while 
Tolles's shows all portions of an object, such as sections equally well, only the cen- 
tral portion of Ross's is clearly defined; with opaque objects the difference is even 
more strongly marked. I showed the four inch to a number of the members cf our 
society on Monday evening, in comparison with Ross's; and there was but one expres- 
sion of opinion, and that of unqualified preference for the Tolles's objective. This 
is a triumph, I think, since Ross's is undoubtedly a very good lens." 
Yours truly, 
W. H. WALMSLEY. 
Extracts from letters from Mr. John May all, Jr. 
"London, Dec. 13, 1875. 
"Mr. Chas. Stodder: 
" Dear Sir, -On taking the lens out of its box a thorough overhaul of the whola 
objective gave me a very favorable impression of the care and precision of the work- 
manship. On that score I don't think that Mr. Tolles has anything to fear from any 
one here. The setting of the lenses, and the correction adjustment, seemed to me to 
be first-rate." 
"London, Jan. 12, 1876. 
" I am not going to enter into a mass of details of the various trials I have made 
with Tolles's l-4th and l-8th. Suffice it to say that no lenses that have been in my hands 
have ever been so thoroughly tested against the best lenses by English, French, and 
German opticians. [He gives a list of seventeen recent immersion objectives by the 
most renowned makers in Europe.] Without reserve of any kind I say these lenses, 
Tolles's l-4th and l-8th, are the finest I have ever seen. . . . I affirm, then, that with 
central and oblique light on all the objects that are known here as tests, Tolles carried 
the palm! I find on the most severe tests there is in Tolles's lenses a bettencorrection 
for spherical aberration. The image is more crisp and clear. By difficult tests, I mean, 
for instance, surirella gemma with central light, or amphipleura pellucida with oblique 
light. On these diatoms the definition is all that I have ever hoped for with lenses of 
their focal length. While on Podura the clearness and .perfect achromatism are be- 
yond anything I can obtain with 's similar powers. . . . The lenses have 
oeen tried by every means known to me. [Here follows the enumeration of thirteen 
methods of illumination.] By all these means I have worked out the problem that 
these lenses of Tolles are first-rate. . . . The lenses have a very precise focus, and 
a particularly best point of adjustment, therefore I say, in my hands, I find them 
easier to manipulate than any lenses I know of, with which any such images can be 
obtained ... I urge that low angle lenses will not exhibit the definition these 
lenses will show, and that if one takes a higher power that will show the images, he 
will find, by comparison, the higher power will be more difficult to manage. The 
whole question turns upon results: if you are content with medium images, use me- 
dium or low angle objectives; if you train your eye for fine images, you must use high 
angle objectives. I find these lenses fairly obey my will, showing images at once 
such as have generally required some minutes of manipulation." 
From Dr. J. G. Hunt. 
" Philadelphia, July 27, 1876. 
" The l-5th that you sent to me two years ago is now in England. It combined in 
the greatest degree resolution of lined objects with penetration. It was the best lens, 
in all respects, for the histologist I ever saw." 
"Philadelphia, Dec. 26, 1876. 
" I can now report that the l-10th you sent to me is grand. It contains more good 
qualities than are to be found in many first-class lenses. Perfect mechanical work- 
manship, large field, gives sharp image on the margin of field, decision of definition 
leaving nothing doubtful or foggy, equal penetration with resolution, thus being 
superior for histological work. I could engrave it all over with marks of admiration! 
. . . For the best work of the botanist or histologist it has a definition which can 
be retained, with an amplification such as I have not yet seen in any l-25th or l-50th 
that has come under my notice. It is plainly seen that its organization was not 
accidental but designed. I see in its construction more finger-skill, more time and 
conscious brain patience, than mathematics, hence its character. It has no precedent, 
but is wholly original and unlike any other make, English or Continental. Thanks.' 
Extract from a letter from an eminent scientist. 
" Birmingham, England, Dec. 20, 1876. 
" It is one of the characteristics of a real work of art that the more closely examined 
the more its beauties shine forth, Surely few modern lenses have been as carefully 13 
looked at as this l-25th you sent me, and I should assuredly say that few have come 
so well out of the ordeal. 
" Four persons, living hundreds of miles apart, have passed independent judgment 
upon it, and I am very glad to be able to tell you,that to make a summary of their 
opinions, all consider that the lens is superior to any objective of similar high power 
yet seen in England. The images are 'bright' and 'robust,' instead of having the 
poorness and flatness usually recognized in most l-16thsand I may say in every glass 
beyond that power. There is an absence too of colored fringes, which shows how 
carefully you have made the chromatic correction." 
From the Journal of the Quckett Microscopical Club, London, Dec. 22, 1876. 
" Mr. Crouch said he hoped it would be thoroughly understood that, in his remarks 
upon the productions of the American opticians [at the centennial exhibition], he 
spoke not as a maker but entirely as individual observer. He had seen some of Mr. 
Toiles's objectives, which he had not seen surpassed in performance anywhere." 
Brooklyn, N. Y., Feby. 15, 1872. 
I have a 1-10 objective made by Tolles. I like it very much. I have resolved the 
amphipleura pellucida with it, which I have never been able to do with any 1-10 in 
my possession (and I have several). I look upon it as a very remarkable lens. 
From Prof. Chas. E. West. 
From the Boston Transcript, March 21, 1872. 
Rev. E. C. Bolles, of the Rust Street Universalist Church, Salem, late of Portland, 
a naturalist of eminence, began his course of lectures last evening. He discoursed 
in an agreeable, off-hand manner upon the microscope, considered historically and 
mechanically, covering in his remarks the two centuries just passed. 
Robt. B. Tolles, of Boston, was pronounced to be, on the whole, and from a most ex- 
tended examination of the field, the most successful maker of microscope lenses, now 
living, in any country of the world. 
From Dr. Jos. G. Richardson's Handbook of Medical Microscopy, Phila., 1871, p. 26. 
"I had an opportunity, not long since, of examining and working for a short time 
with an immersion 1-10 made by Mr. Tolles, which performed better than any other 
objective of its focal length that 1 had previously seen. When accurately focused, 
the working distance, although small, was ample, being nearly twice that of the 
1-25; the magnifying power was fully equal to the standard (500 diameters); the defi- 
nition very superior; the penetrating power, as tested upon a light Podura scale, 
very good; its field perfectly flat, and the image formed by it entirely free from 
chromatic aberration. It was mounted for use either dry or immersed, and when 
employed in the latter condition defined well with deeper eye-piecing than any lens 
I ever saw before, showing upon my Powell & Lealand stand, with their No. 4 eye- 
piece. the limiting membrane and revolving molecules of the salivary corpuscles 
with remarkable clearness. The price of such a glass of 160° angle of aperture is 
$80." 
Extracts from the proceedings of the Boston Society of Natural 
History, vol. xii, p. 359. Hr. Hagen, of Cambridge, said: 
"All over the world, first-class microscopes have resolved 
the fourteenth, or even the fifteenth [?] band of Nobert's test 
plates ; but should it be found that American microscopes, even 
with a one-eighth objective, have resolved perfectly the nine- 
teenth band, the superiority of these instruments would be so 
enormous that it could be easily proved at any time and place." 
This had been done repeatedly with several objectives made 
by Tolles, at the time Dr. Hagen made the above remarks. It 
has often been done since with other objectives made by Tolles, 
and can be repeated at a suitable time and place ; but not with 14 
any objectives taken at random, but only such as are made for 
that kind of work, - not easily, for it requires the most deli- 
cate manipulation. 
Since that time, Dr. Hagen has himself seen and counted 
"about forty" of the lines of the 19th band, with a Toiles's 
1-10 immersion objective. " The lines were well defined."- See 
his communication to Max Schultz's Archive for Microscopische 
Anatomie, 1870, No. 2. 
Extracts from " Remarks on Resolution of the XIXth band of Nobert's Plate, by certain 
objectives, especially by a new Tolles's immersion l-18th." By Dr. J. J. Woodward, 
U. S. Army. Monthly Microscopical Journal, London, Nov. 1872, p. 227. 
" This objective is so surpassingly excellent on the plate, that I hasten to make the 
facts public, as promised." "With regard to the performance of the dry combina- 
tions of this objective, I will merely say that they gave me the striae of Amphipleura 
pellucida rather better than any dry objective I have ever tried " "The behavior 
of the objective when used wet, is certainly admirable. In illustration I forward a 
series of views of Nobert's plate from the lowest to the highest taken by it. These 
pictures certainly excel all my former work on the plate." "It will, of course, be 
expected that I should say something of the comparative merits of this new objective 
of Mr. Tolles, and the immersion front of the Powell & Lealand l-16th, which has 
done such good work for me since 1869. "Certainly 1 must give the new Tolles's 
objective the preference on the plate, and on Amphipleura pellucida, both by sun and 
lamp light." "I have next to state that Mr. Tolles having been kind enough to send 
to me during the past year a number of objectives from l-10th to l-20th, for study, I 
have since Feby. of the present year satisfied myself that several of them resolved 
the 19th band in a very satisfactory manner." 
Extract from a letter from a well-known microscope maker. 
London, Sept. 25th, 1872. 
" One of my customers has requested me to procure for him your l-10th objec- 
tive. 
Prof. Markoe, of Boston, was kind enough when at my place a few weeks ago, to 
show me the performance of this lens, which I believe, from what I saw of it, to be 
the finest objective of this description I ever had the pleasure of looking through." 
J- s -. 
From a letter from the Register General, Melbourne, Australia, July, 1873. 
"My interest has been much excited accidentally by a chance conversation with a 
gentleman I met recently, who told me that he had heard at home that in mechani- 
cal and optical skill Mr. Tolles was bearing away the bell against the first of European 
competitors." 
Report of the Judges on Philosophical Apparatus, eleventh 
exhibition of the Massachusetts Charitable Mechanic Associa- 
tion held in Boston, September,1869. Joseph M. Wightman, 
Esq., Josiah Curtis, M.D., Chas. K. Stevens, Esq., Judges. 
Nos. 297 and 460. Boston Optical Works, Boston. Robert 
B. Tolles, Superintendent; Charles Stodder, Treasurer. Micro- 
scopes and Telescopes. The Microscopes exhibited comprise 
a variety of instruments and accessories, embracing much that 
is original and ingenious, and characterized by nice ><nkuian- 
ship and elegance in appearance. 15 
One large microscope, with A and B Huyghens' eye-pieces, 
and Toiles's patent solid C eye-piece, with micrometer, lias a 
very ingeniously constructed rotary stage, devised by Mr. 
Tolles, which is only one-sixteenth of an inch thick. Its rotary 
movement is concentric with the axis of the objective. It has, 
also, lateral movement by friction rollers, and a sub-stage, 
movable by rack and pinion, for accessory apparatus. 
In the list exhibited we find a binocular eye-piece and a 
solid eye-piece, both invented by Mr. Tolles; and although the 
latter was patented in this country by him several years ago, 
we were shown a similar device, in fact nearly identical in every 
essential particular, by a scientific friend who has just returned 
from a sojourn in Europe, where he purchased it as a new and 
valuable oculaire, one of the latest improvements just invented 
by a microscope maker of celebrity in Paris. 
The judges took as much pains as circumstances permitted 
to compare the workings of the instruments on exhibition with 
others of the most reputable makers in this country and Europe. 
The objective of the highest power was the one-tenth immer- 
sion, whose angle of aperture is 175°. Under the observation 
of the judges, and others whose assistance was invited, this 
objective defined test objects better than any objective of the 
same power, and as well as many others of higher powers, from 
other makers which were at their command. The usual tests 
were resorted to, such as the Pleurosigma angulatum, Suri tell a 
gemma, etc., etc., among the Diatomaceoe, and Nobert's test 
plate from artificial sources. The latter is, par excellence, the 
test of the quality of objectives. It consists of straight lines 
uniformly ruled on glass, and is not subject to the variations 
which prevail in different individual specimens of the same 
species among natural objects. The test-plate used was one of 
Nobert's later make, containing nineteen bands, the last of 
which, on the nineteenth band, was composed of lines so fine 
and close that it requires over 112,000 to occupy the space of 
one inch. These were clearly resolved by direct* light illumi- 
nation from a kerosene lamp, with the one-tenth immersion 
objective! and a B eye-piece. Among those invited who wit- 
nessed this performance may be named Prof. Walcott Gibbs 
and Dr. B. A. Gould, of Cambridge. The true lines of this 
* Direct light should not be confounded with central light. The light was direct 
from the lamp, unmodified; of course it was very oblique. 
t This is the same instrument referred to by Dr. J. J. Woodward, in his paper in 
the " American Journal of Science " for September, 1869, and in a communication to 
the " Monthly Journal of Microscopical Science," London, for December, 1869, and 
called by him an eighth only. 16 
nineteenth band have never yet been seen by Nobert himself, 
and their resolution has been pronounced, both by him and many 
European microscopists of eminence, as physically impossible. 
We cannot learn that any one in Europe claims to have seen 
them, if we except, perhaps, Nachet, of Paris. At the U. S. 
Army Medical Museum in Washington, D. 0., with a one-six- 
teenth immersion objective, made by Powell and Lealand, of 
London, the sunlight being controlled by a heliostat and ren- 
dered monochromatic, excluding all rays of the spectrum except 
those of the shorter-wave length, and condensed with a one- 
inch objective of Toiles's make, the lines in question have been 
photographed. 
The binocular eye-piece is also the invention of Mr. Toiles. 
It not only seems to do well what any other form of binocular 
microscope will do, but it is also suitable for use in those cases 
where all other binoculars fail, their uses being limited to the 
lower powers in consequence of the relationship of their binoc- 
ular arrangement to lhe objective. Mr. Tolles's arrangement 
connects it with and makes it a part of the eye-piece. It may 
also be used with telescopes. 
The telescopes on exhibition by the Boston Optical Works 
comprise one Improved Equatorial Telescope, having live inches 
aperture and thirty-five inches focal length with two eye-pieces 
having powers of 80 and 160 diameter respectively; and two 
smaller improved short-focus telescopes. Of the latter, the 
lens or object-glass of one is one inch in diameter, and has a 
focal length of four inches. The extreme length of the instru- 
ment is twelve inches. It has a pancratic eye-piece, varying 
the power at will, and is reported to have borne one hundred 
diameters with full satisfaction. The other has one and a half 
(1.45) inches aperture, and six inches focus. 
It will be at once observed that the shortness of lengths for 
such apertures is novel, if not unique. It is believed to be 
without a parallel in instruments from any other maker. 
In conclusion, it should be stated that none of the articles 
above noticed were made for exhibition, but faithfully represent 
such as are put into the market. Indeed, nearly all of them 
have been sold, and were loaned by their owners for this occa- 
sion. It may also be added that the opinion of the owners, as 
well as others eminently capable of judging correctly and im- 
partially, emphatically justify the conclusion of the judges in 
deeming the articles from the Boston Optical Works worthy of 
the highest reward, a - 
GOLD MEDAL. 17 
Extracts from the report of Dr. F. A. P. Barnard, LE. D., 
President of the Columbia College, N. Y., Commissioner of 
the United States to the Exposition Universelie, Paris, 1867. 
P. 152. "In no branch of physical investigation has the 
number of zealous devotees in recent years more rapidly in- 
creased than in the study of microscopical organisms ; and no 
instrument of optics has occupied in its construction a larger 
amount of practical skill of the highest order, or has received 
more numerous and more important improvements than the 
microscope itself. It is, indeed, the high perfection and won- 
derful power of this instrument as at present constructed, which, 
by affording clear and satisfactory views of the structure of 
only recently esteemed excessively difficult and doubtful objects, 
and by thus diminishing immensely the labor of microscopic 
research, has given to it its present great and rapidly increasing 
popularity." 
P. 534. "The objectives of Mr. Tolles are unsur- 
passed BY ANY IN THE WORLD." 
P. 237. "It is not necessary for Americans any longer to go 
abroad in order to obtain microscope glasses of any description 
of the highest order of excellence." 
P. 541. "Mr. Tolles has constructed an instrument on the 
stcreotomic principle, designed to remedy the difficulty attend- 
ing the original binoculars, while at the same time it secures 
the incidental advantage of permitting any ordinary single-tube 
microscope to be used as a binocular. . . . This eye-piece 
works with objectives of all powers with perfect equality of 
illumination in both fields. 
"Mr. Tolles has also produced very fine stands. A master- 
piece of this kind, constructed by him from designs furnished 
by the present reporter, possesses some important and peculiar 
advantages." 
No instruments were sent to the Exposition by Mr. Tolles; 
some of his friends contributed their objectives of his make, all 
"dry working," but there were no "stands" provided on which 
to exhibit them. Notwithstanding this great disadvantage, the 
jurors awarded to Mr. Tolles for the objectives the - 
SILVER MEDAL. 18 
TOLLES'S DUPLEX ONE-TENTH. 
From the "Journal de Micrographic." Paris, March, 1878. 
We have received a great many demands for particulars regarding the famous l-10th 
objective of Mr. Tolles. ... As to tlte optical quality of this objective we have 
but a word to say about it: it is the finest that we have ever seen. It resolves 
with incomparable clearness all the known tests. ... To conclude, we do not hesitate 
to affirm that we consider this instrument the finest objective in the world; also, we 
think its high price ought not to be an obstacle to its being made common among 
French microscopists, to whom we recommend it in preference to any other. 
TOLLES'S ONE INCH AND FOUR TENTHS OBJECTIVES. 
From the ''Journal de Micrographic." Paris, May, 1878. 
We were astonished for a time at the high prices of the low-power English and 
American objectives from four inches to one third of an inch; we confess we could 
scarcely comprehend that such lowpowers should necessitate.such costlyinstruments; 
that we could only with difficulty admit that one should devote from 100 to 200 francs 
in purchasing objectives that one could buy for 20 or 30 francs of Hartnack. or Zeiss, 
or Nachet. For a long time we have seen our error, - in part, at least, - and we have 
already many times confessed it, in regard to the 4-10 of 90° of Beck, - but we see 
every day how greatly we were deceived, and m examining some of the preparations of 
Chas. Zentmayer with the 1 inch and 4-10ths of Tolles, we have had a new and start- 
ling demonstration of our mistake; of the 4-10ths of 80° we have not more to say, 
except that in rivalry with Beck's (which is a true 1-3, and therefore gives a. larger 
amplification) it gives a fineness of image incontestably superior and a penetration 
still greater than the fine objective of Mr. Beck. 
But the one-inch of eight lenses of Mr. Tolles has veritably astonished us by its 
totally unexpected qualities. 
If one examines with one of our (French) best objectives by one of our best makers 
a preparation of a certain thickness, one of two things happens: either the objective 
is of small angle and permits more or less incomplete view of a certain depth of the 
preparation of which the contours are notcharp nor the illumination brilliant, or the 
objective is of large aperture and one sees a very slight depth or plane (if the instru- 
ment is good), of which the outlines are sharply shown and the illumination brilliant; 
to observe the different layers, it is necessary to focus, and one thus sees a series of 
superposed planes showing perfect inages, but spiritless. 
But with the one-inch or Tolles wo see not a plane, but a picture with a deep per- 
spective, with the outlines finely engraved and brilliantly illuminated; that is to say, 
this is one of the objectives called penetrating: but objectives can >mly have penetra- 
tion with a narrow aperture - this has 30°. We have, then, an object-glass of very 
wide angle (for 30° is the widest angle possessed by any one-inch, of our acquaintance 
at least), consequently giving a large, brilliant field, an image of which the details are 
as visible as is possible with soTow a power, of which the contours are of an extreme 
fineness and sharpness, and which with all this possesses " a penetrating power " such 
as to produce the effect of a binocular. 
" It is impossible ! " one will-say. Yes, it is impossible, we know it well; but it is 
none the less real. And we now see why we have reason for saying that this objective 
has plunged us into a profound astonishment. 
TOLLES'S STEREOSCOPIC BINOCULAR EYE-PIECE. 
To the Editor of the " Monthly Microscopical Journal." 
Hobart College, Geneva, N. Y., U. S., May, 1871. 
Str: - I wish to correct as widely as possible, a statement in regard to the stereo- 
scopic binocular eye-piece, which attributes the invention to me instead of Mr. Tolles, 
to whom really the whole credit belongs. Dr. Carpenter * has made, unintentionally, 
such a statement, and it has also been made by others.f I doubt not it will bo rectified 
in future editions. This misstatement wasuin known to me until within a few weeks. 
If it had been known I should have made the correction promptly.. It is not difficult, 
perhaps, to account for the mistake, inasmuch as I first exhibited this eye-piece in 
England at the soirees of the Microscopical Society and the Royal Society, and to 
numerous individuals, among them Dr. Carpenter himself, who expressed his satis- 
faction at its performance. Mr. Ladd, the well-known philosophical instrument 
maker, 11 and 12 Beak Street, Regent Street, had it for some time,in his possession, 
and indeed made one, which, however, was much inferior to Mr. Toiles's, as Mr. 
Ladd had not time to determine the proper curves, if indeed the lenses were achro- 
* " The Microscope," 4th ed p. 35. t " The Microscope," by J. Hogg. 7th ed. p. 119. 19 
inatics at all. Ho understood, however, that it was Mr. Toiles's eye-piece; and I 
have by me the original " exhibitor's card," and at one of the soirees named, reading 
distinctly, " Toiles's binocular eye-piece, exhibited by Prof. Smith." I feel very 
anxious to have the mistake corrected. 
The first eye-piece of this form which Mr. Tolles ever made was purchased by me, 
ami 1 gave some account of its performance and peculiarities in the "American 
Journal of Science," July, 1864, p. 111. And, in the same journal shortly after, Mr. 
Tolles himself described its construction. Now, although we cannot expect every 
one to read an American journal, or to be posted in all that is done this side of the 
Atlantic, even in the microscopic line (except to notice the trash, e. g. the mean 
little sheet issued by manufacturers and sellers of the Craig microscope! ! ! recently 
attempted to be palmed off as the organ of the Illinois Microscopical Society), it is a 
little surprising, considering the length of time these two articles have been published 
in a most prominent journal, that such a blunder should occur. Of course it is inad- 
vertence. Dr. Carpenter, I am quite sure, is ready and willing to do full justice, and 
in so doing, it will be proper to state the real principle of the eye-piece in question. 
It is not, as he has stated, I. c merely an arrangement of prisms, similar to MM. 
Nachet's, for in reality the prime part of the eye-piece may be this, or Riddell's, or 
Wenham's; and, in fact, in the first eye-piece made for me was different from either 
of these. Mr. Tolles finally - partly at my suggestion, though I believe he had 
already decided upon it - adopted the Nachet form, and he claims nothing for this. 
What he does claim, and is justly entitled to claim, is the construction of a first-class 
achromatic erecting eye-piece, and a division of thy pencil, for stereoscopic vision, at 
or very near the point of crossing of the rays in such a combination. Now it is well- 
known that the difficulty in using the Wenham or Nachet arrrangement with high 
powers, arises from the necessity of dividing the pencil so far behind the objective, a 
difficulty it seems cannot be got over, except upon Mr. Tolles's plan, viz.: making a 
secondary image, and dividing the pencil here, or near the point of crossing of the 
rays. The binocular eye-pieces invented by President Barnard, and by myself, are 
simply binocular, like Powell and Lealand's arrangements for high powers; though 
superior as to equality in illumination of the two fields, they are not stereoscopic. 
Perhaps the fact of my having made such an eye-piece, and published an account of 
it, as also Dr. Barnard's notice of it, in his report upon the Paris Exposition, may 
have assisted to mislead in attributing the really stereoscopic binocular of Mr. Tolles 
to me. If I had been the originator of eye-piece, which is yet destined to replace 
most binoculars, I should feel I had contributed a much greater boon to microscopy 
than any I have yet done. The instrument as made now by Mr. Tolles is very per- 
fect; the loss of light is trifling, easily remedied by a little more illumination. The 
loss in definition is not so much as in the Wenham and Nachet forms; not merely 
from the care with which Mr. Tolles works the prisms, but owing to the much 
shorter distance which the reflected ray has to travel. This part of Dr. Carpenter's 
objection is practically without force. The eye-piece is expensive. Not only is it, at 
least so far as regards all below the prisms, perfectly achromatic, but of very pecu- 
liar and perfect construction, and as to liability of derangement, I can safely say it 
is as firm as any binocular arrangement now known, and easily adjusted if it should 
become deranged. I am told that M. Hartnack has made a similar eye-piece. Dur- 
ing the Exposition, I placed Mr. Tolles's eye-piece in his hand for inspection, and 
it remained with him for several days. I cannot say whether he copied it, or whether 
his arrangement is different in principle, or the same, as I have not seen it. M. 
Hartnack appeared to me to lie far too honorable a man, as MM. Nachet, to whom 
also I showed it, most certainly were, to take any credit for an invention truly belong- 
ing to another. 
H. L. SMITH, 
Formerly of Kenyon College. 
[.From the "English Mechanic" London, May 9,1873.] 
A correspondent says: - 
"I am sure that "Binocular" will be glad to learn that there is a binocular eye- 
piece that is in my opinion infinitely superior to Mr. Wenham's arrangement, both 
for the microscope and telescope. The binocular eye-piece I refer to is the invention 
of Mr. Tolles, of Boston. It differs from Mr. Wenham's in that the cone of rays from 
the object-glass is divided at its apex by a prism placed just in front of the field- 
lenses of the two eye-pieces. . . . I wrote on this subject in the " Astronomical 
Register," some years ago, as also did Dr. Huggins, I think, in the third volume. 
. . . I tried to get some of our opticians to adopt this plan, but they had been 
putting double bodies to their microscopes, and evidently did not wish to have to take 
them off again. I have tried Mr. Toiles's eye-piece with my telescope, and found it 
to answer admirably, especially on the moon." 
(Signed) VICAR 20 
REPORT ON TOLLES'S OBJECTIVE. 
Wayland, Steuben Co., N. Y., Sept. 23, 1873. 
Dear Sir: I commenced using the Tolles's l-50th objective by thinking well of it 
and find it improves on acquaintance. This lens has remarkable ilatness of field 
combined with excellent defining and resolving power, plenty of light, and good 
working distance. It works well through covers l-200th of an inch thick. To-day, 
with a small German student lamp, and the beam direct from the lamp, without 
mirror, prism, or condenser, and no tricks, I resolved with the l-50th Amphipleuvapel- 
lucida into the transverse stria, seeing the lines with No. 1 eye-piece x 2,500; No. 2 
eye-piece x 4 000; and finally, with No. 3, power 7,000 diameters. With the deep eye- 
pieces. the edges of such tests as Pleurosigma ongulatum are well defined, without the 
indistinct and woolly apuearanco usual with such high powers. 
In examining the organisms in water, the concave mirror gives ample light. The 
ultimate resolution of A pcllucida and the various varieties of Navicula rhomboides 
into dots and squares, using blue light gives further proof of the exquisite perform- 
ance of the lens. Its superiority is equally marked in the study of the structure and 
growth of minute living organisms. 
Many more facts might be given in praise of this glass. 
GEO. W. MOREHOUSE. 
TOLLES'S IMPROVED TELESCOPE. 
The Pedestrian's Telescope. - An instrument not too 
bulky to be carried in the pocket, and of sufficient power and 
definition to be worth the trouble of carrying, has always been 
a desideratum with the tourist. Mr. Tolles has now produced 
such an instrument, on his improved system; it has a 1-2 inch 
object glass, with his patent solid eye-pieces ; 4 inches long 
closed, G 1-2 inches open; and weighs with a stand, and screw 
for attaching it, four ounces only. Power 10 to 18 diameters, 
being, it is believed, the most portable and efficient instrument 
yet produced. Price $25. With stand, $33. 
The One Inch Telescope is only 4 to 5 inch focus, has a 
pancratic eye-piece, varying the power from 12 to 24 times (to 
which higher powers can be added at an additional expense). 
This terrestrial telescope, in virtue of the plan of construction, 
gives increased light, - on a stand with universal motions, - to 
screw into any wood structure. Price $70. 
Tiie High School Telescope.-A most desirable instru- 
ment for residences on the sea-shore or mountains, and for high 
schools. Tolles's Improved Telescope ; 2 1-2 inch object-glass, 
23 to 27 inch focus, on iron tripod, with motion in altitude, 
and azimuth. Price, with pancratic eye-piece, giving variable 
powers from 23 to 46 diameters, $175; with two astronomical 
eye-pieces, amplifier, diagonal prism, and sun-glass, powers 
from 23 to 130, $250. Telescopes have been supplied to 
Washington Academy, East Machias, Me.; Dr. J. R. Nichols, 21 
Haverhill, Mass. ; Howland School, Union Springs, N. Y. ; 
J. R. Lowric, Warriorsmark, Pa. ; Prof. J. Lawrence Smith, 
Louisville, Ky. ; New Bedford, Mass., High School ; M. Moore, 
Trenton Falls, N. Y. ; Ed. E. Rice, Chas. W. Parker, N.J. 
Bradlee, and John Quincy Adams, Boston; J. J. H. Gregory, 
Marblehead, Mass., and others. 
Having been engaged in telescopic observations for the past eight or ten years, with 
instruments of various apertures, between 1-2 and 3 1-4 inches, I thought that 1 would 
communicate to you the results of a few observations which I lately made, with one 
of the new, improved, short-focus telescopes of 21-2 inches aperture, 23 inches focus, 
with a celestial eye-piece magnifying 45 diameters, constructed by Mr. R. B. Tolles. 
This telescope readily shows Polaris double; it appears as steady as Titan does in my 
48-inch achromatic, with a power of 81. It shows very finely the four principal stars 
in the trapezium of Orion, also Mizar, Beta Cygni, and other superb double stars. 
The view it gives of the great nebula of Orion is magnificent. The elliptical nebula 
in Andromeda was well seen. Various clusters of stars in the milky way were exhib- 
ited in great splendor. Rigel I saw double, which I consider a pretty severe test. 
The planet .Jupiter was a beautiful object, its oblate figure being so very apparent 
that one unaccustomed to telescopic observation would readily perceive it; the equa- 
torial belts were shown very distinct and sharp; the satellites appeared round and 
very distinct, the difference in their size very apparent. Saturn is also a splendid 
object; the principal division in the ring is shown all round. I saw the inner dark 
ring where it crosses the ball; also the equatorial belts and the shadow of the ball, on 
the ring; two satellites, with a glimpse of a third, that I am confident of. 
The short focal length of this telescope I consider to be a great advantage, making 
it more portable, and much more easily directed to a celestial object. The instru- 
ment is mounted on a firm cast-iron tripod, with appliances for keeping it in position. 
It shows all the objects enumerated here far better than a similar power in my 48- 
inch glass, which has a clear aperture of 3 1-4 inches, and which I consider a good 
glass. Since making these observations I have bad the loan of another telescope, 
made on the same principle, but with an object-glass only 1 inch in diameter, and 4 
inches focal length, furnished with a pancratic erecting eye-piece, magnifying 24 
times. Its performance is wonderful. It shows Saturn well, but with terrestrial 
objects, its definition is superb. It is mounted on a universal joint, with a gimlet 
screw to fasten it to a tree, fence, etc. 
I should have made a comparison between these two large instruments with the 
same eye-piece, but had no appliances convenient to fit the Tolles eye-piece on my 
instrument; but from my experience, I consider the Tolles glass the superior instru- 
ment, the field being very dark, instead of gray, as in other instruments. I have 
never seen any small telescope perform equal to the 2 1-2 or 1 inch. 
WILLIAM H. PHELPS. 
- Boston Journal of Chemistry, October, 1870, p. 40. 
A NEW TELESCOPE. 
TOLLES'S FIVE-INCH TELESCOPE. 
Extract from a letter of Dr. B. A. Gould, Cordoba, S. A., April 24, 1871. 
" The star of Eta Argus has naturally attracted a good deal of my attention. It is 
at present not far from the 6 1-2 magnitude and recognizable with great difficulty by 
the naked eye. In the field of my small Toiles's telescope of 5-in. aperture, and 35 in. 
focal length, it is a conspicuous object, and prominent by its ruddy color among the 
cluster of which it forms a part. . . . With this telescope, the same one wlrch I 
employed for observing the total eclipse of 1869, I have been examining the whole 
group; and have found to my astonishment that it exhibits with distinctness a con 
siderable number of stars, which are recorded in Sir J. Herschel's catalogue of this 
cluster, as being of the 15th magnitude. 
The magnificence of the milky way in this vicinity is indescribable, surpassing the 
Pleiades or the Praesepe in richness, and exhibiting numerous huge clusters, the 
eight of which through the Tolles telescope evokes exclamations of astonishment and 
delight from every beholder, young or old, whether with or without astronomical 
information." - Am. Jour. Science, July, 1871, p. 80. 22 
Boston, Nov. 30, 1874. 
Mr. Charles Stodder: 
My Dear Sir, - It will give me much pleasure to have the telescope which Mr. 
Tolles has just made for the Argentine Observatory exhibited publicly, provided it 
can be. ready for shipment when needed. The similar instrument which he made for 
me about a dozen years ago has been and is to the best of my belief unequalled in 
its peculiar advantages. For telescopes of five-inch aperture about fitfy-five to 
fifty-eight inches has been deemed the shortest focal distance compatible with good 
achromatism and sharp definition. But this one, although it has the wonderfully 
small focal distance of only thirty-four inches, possesses great excellence of definition 
and a portability unexampl d for an instrument of its optical power. 
Its field of view, when used with its lowest powers, is 2° in diameter, and this singu- 
larly large area proved of special importance in observing the total eclipse of the sun 
in 1869, enabling me to see not only the whole corona with the advantage of an 
amount of light probably 1,500 times greater than would have entered the pupil of the 
unaided eye, and to take note of its variations of form during the progress of the 
eclipse, but at the same time to subject the region around the eclipse to a survey 
sufficiently careful to assure me that no star so bright as the.four and one half magni- 
tude was to be seen within the orbit of Mercury. 
The telescope has been in frequent use since I obtained it, and has rendered impor- 
tant service in both hemispheres. Its value for examining nebulae and star clusters 
with low powers is unsurpassed, and I have never seen a portable instrument which 
could compare with it in efficiency. Not more than a couple of minutes are required 
for taking it from its box and placing it in adjustment upon the posts which are 
always standing ready to receive it, on or near whatever house I may inhabit. Its 
equatorial mounting permits it to be directed without delay to any celestial object 
whoso place is known 
My attachment to and pride in that instrument are so great that, although it is now 
at tlie Cordoba Observatory, I am unwilling to part with it permanently, and have 
therefore induced Mr. Tolles to construct for the Argentine Government this new 
one, as nearly similar as may be. I anticipate for it equal excellence, and doubt not 
it will prove its eminent maker capable of attaining in the construction of telescopes 
a reputation not inferior to that which he enjoys throughout the scientific world as 
the maker of microscopes which, to say the least, are inferior to none. 
I am very sincerely yours, B. A. GOULD. 
TOLLES'S FOUR-INCH TELESCOPE. 
Canandaigua, N. Y., Aug. 2,1878. 
Mr. Charles Stodder, - Last December I purchased of you one of Toiles's 
Improved Telescopes, 4 1-10 inch object-glass, focal length 42 inches, mounted on iron 
tripod, with motion in altitude, and azimuth. I wish to say that I am highly pleased 
with its performance. I consider its short focal length as great advantage; it is so 
easily handled, and readily turned upon any object. Its mounting 1 consider perfect, 
motion perfectly smooth, and it is easily adjusted to any position. 
I mention a few of the objects which 1 have seen. Its definition of Venus in its 
crescent pleased me very much. I can plainly see five stars in the trapezium of Orion, 
and when the air is very favorable, I am confident that I have seen six. Kigel's com- 
panion is quite conspicuous, and 1 have seen Aldebaran double. .Jupiter is a mag- 
nificent object, belts and satellites very distinct. I have not had an opportunity to 
test it on the rings of Saturn, though I saw them as a line of light until within three 
days of their predicted disappearance. With eye-pieces of low power it presents star- 
clusters beautifully. I enjoy it very much, and prize it highly. 
Since writing the foregoing I have had an opportunity to look through one of ****'s 
6-inch telescopes. I think my Tolles 4-inch is superior to it in defining power, and 
very nearly, if not quite equal to it in other respects. I prize mine still more highly 
by reason of the comparison. 
Respectfully yours, 
D. SATTERTHWAITE. 
Extract from a letter dated Loudon, Vdth July, 1878. 
Mr Charles Stodder: 
Dear Sir,- The i and j objectives that were in Mr. Mayall's hands were pur- 
chased by me. . . . Both these lenses are, in my judgment, superior to anything 
made this side of the Atlantic. . . . Still I am wanting a fine high-power lens, and 
if there is anything better in the world to be had, I think Mr. Tolles is the man to 
do it. 23 
From " Mount Washington in Winter," Prof. J. II. Uantington. 
" That bright line extending so far along the coast is the ocean; but we can rarely 
see it with the unaided eye, except where the waters reflect the sunlight; and then 
with a Tolles telescope, having an object-glass of one inch, and focal length of four 
inches, wo can not only see vessels as they sail along the coast, but can distinguish 
their rig." 
From Thos. Birt, Troy, N. Y., Jan. 9th, 1871. 
" I have used the 1-inch telescope a number of times, and find it a complete thing. 
The glass for terrestial observation is superb; for celestial, very good for so small an 
one." 
All correspondence and orders for Toiles's instruments must 
be addressed to 
CHARLES STODDER, 131 Devonshire St., Boston. 
Charles Stodper is authorized by the publisher to receive 
subscriptions for the "Quarterly Journal of Microscopical 
Science." 
"Journal of the Royal Microscopical Society," bimonthly, 
$6, by mail. 
" Journal de Micrographic," Paris, by Dr. J. Pelletan. $6.00. 
"Journal of the Quecket Club," London. 50 cents per num- 
ber. 
The "American Journal of Microscopy," monthly, $1.00 per 
year. 
Every student desirous of keeping up with the progress of 
microscopical science ought to have one of the periodicals which 
record the new discoveries. SELF CENTRING TABLE. 
THE BEST IN USE. $6.50. CEE ARLES STODDER, 
131 DEVONSHIRE STREET, 
Room 36 BOSTON, 
KEEPS IN STOCK 
Apparatus, Material, Instruments, and Books used by Microscopists. 
Microscopes and Objectives, by Zentmayer, Wales, and others, in 
stock or made to order. 
Second-hand Microscopes and Objectives. 
Agent for Rogers' Micrometers and Test Plates. 
Stage Micrometers, inch, $1.25 to $2. 
" • " T<lo5 Tata, S'ouny inch, $1.75 to $2. 
" " millimetre, $2.50. 
" " -j-'j, -pHj-, Tolyjy millimetre, $5. 
Eye-piece Micrometers, $2 to $6. 
Special price list for other ruling. 
Willis' Heliostat, $30 to $35. 
Whirling Tables. $2 to $6.50. 
Patent Plate Slides, ground edges, 3x1, 40c. per doz 
Thin Glass, circles, $3.50 to $5 per oz. 
" " square, $2.50 to $4 per oz. 
Live Boxes, $2 to $8. 
Dipping Tubes, Pippets, Test Tubes, 5c. to 15c. 
Polariscopes for the Microscope, $15 to $50. 
Wenham's Parabolic Condenser, $14. 
Dissecting Microscopes, $14. 
Beale's Capillary Bottles, 45c. 
Browning's Microspectroscope, $50. 
Book.Cabinets, to hold 50 slides, $1.25. 
Gold Size, Glycerine Jelly, Canada Balsam, Chloroform Balsam, and 
other articles for mounting, at lowest prices. 
A large variety of mounted objects for the Microscope, Anatomical, 
Pathological, Botanical, Diatoms, etc., including Julien's and 
Dickerman's Rock Sections, Dr. Hunt's Botanical, and a few by 
the late Edwin Bicknell. 
Agent for, Cheyney's Chemicals and Preparations for staining and 
mounting. 
BOOKS. 
How to Use the Microscope. Phin. 75c. 
Carpenter on the Microscope. Fifth Edition. $5. 
Frey. Text-book for Physicians and Students. $6. 
Wythe on the Microscope. $4.50. 
Manuel D'Histologie Normale. Part I. By Dr. J. Pelletan. Paris, 
1875. The latest work on Histology. $1.50.