-^>-9
INTRODUCTORY ADDRESS
Course of HUbital  lectures,

GEORGETOWN  COLLEGE,
NOVEMBER 3, 1863.
 
 
INTRODUCTORY ADDRESS
€anxst  of  Illegal JTtriuns,
GEORGETOWN  COLLEGE,
NOVEMBER 3, 1869.
By SILAS L. LOOMIS, A. M., M. D.,
      PROFESSOR OF PHYSICS AND CHEMISTRY.
     WASHINGTON:
K'OILL 4 WITHEROW, PRINTJSR8,
        1862. 
 
ADDRESS.
                       —«>■
Gentlemen :
  We may well congratulate ourselves that, in the midst of
such a convulsion as now agitates our country, when to such
an extent the arts of war have  supplanted those of  peace,
we are  met under  circumstances so auspicious, to inaugu-
rate  our Course of  Lectures.  Untouched by the shocks of
civil war, its carnage and devastations, we meet to  renew
again our quiet investigations in the arts of healing and
relief of suffering.
  Especially may we congratulate those who are now enter-
ing upon  these studies.  Amid these lurid clouds, shines a
favorable sun for those who would learn to touch with magic
wand and power, the ills to which humanity is heir.  Many
circumstances combine to render this a favored hour—an
hour of privileges, opportunities, and responsibilities.  And
to us, to you young gentlemen, located within the lines of
the  army, as it were upon the very field of battle,  whose
smoke has scarce been rolled  away, ere its unfortunate vic-
tims are brought to your feet for the healing balm that shall
keep the quivering pulse still in being, or  for the sterner
purpose of severing the living from the dead—to you espe-
cially, is this a propitious hour.  To be thus situated is to
enjoy a privilege rare indeed, and which, while we prize, we
may trust, and pray may not be ours or yours again.
  But these special privileges come not without  their cor-
respondent responsibilities and obligations.  Humanity has a
right to demand, and does demand that such a grand experi-
ment of human endurance, capability, strength,  sickness,
accident, and  death, shall not pass  without its great lesson
to the medical  profession.  If Hygenia finds in Mars  her
most implacable enemy, she nevertheless must, in justice,
acknowledge him  her most lavish patron.  This is no hour
of idleness.  If the profession is true to itself, true to this 
4
age and  its crowding events, the present decade must wit-
ness a decisive advance in American  surgical and  medical
science.
  But there are other reasons besides these already alluded
to, why we are standing at the threshold of such a promising
future.   The perfection of the Microscope and of chemical
tests, have reduced the  basis  of medical knowledge from
theory to demonstration,  from  the vagaries of  imagination
to the immutable certitudes of truth.   And when the human
mind has once laid  bare  the great foundation truths, slowly
but securely with every new demonstration rises the majestic
and imperishable temple  of science.
  Kot that the past has not  well fulfilled its.mission.  Kay
much has been done and well  done; and when we may number
but little less than a thousand published works on the subject
of Materia Medica alone,  we  may well be assured that, taken
in all its departments, few branches of knowledge have made
a more honorable record for itself than the Medical.   Yet
honorable and voluminous as is this record, we must  not for-
get that the rapid progress of recorded  discovery has  largely,
and must soon more, widen the distance between these works
and  us.  They were valuable  for the  times they were  in-
tended to instruct, but valuable to  us only so  far as their
instructions will stand  the test of the  microscope and the
crucible.  The present is, therefore, almost a new instauration
of the sciences of Organic Chemistry, Pharmacy, and Physi-
ology. The introduction  of the microscope into these depart-
ments has been the most important step taken in the history
of these sciences.
  Books,  therefore, lie necessarily  behind the  profession.
Each year brings its generous accumulation of newly estab-
lished truths, made known through journals and magazines.
These, therefore, must  stand between  the library and phy-
sician; but r.either  the one  nor the other, can  nor  should,
keep pace with the persevering intelligent seeker of truth.
  Science is but  the collection of nature's laws, as discovered
in the various researches  of men of all ages.  Books, there-
fore,  must be the substantial  basis of the intelligent, the 
5
successful physician; and yet he, who at this day, comes no
nearer to nature than to see through eyes of others will soon
find himself pushed aside  by his living compeers, and laid
upon the shelf as a fossil of the past.
  One course alone  lies open to the student in this stern,
incredulous age of tests and micrometers.  It is the old fable
of (Edipus and the Sphinx, he must guess the riddle or be
devoured.   Reverting  back to  those first principles  that
admit  no question, that are received as acknowledged truth,
rejecting all that is  speculative or  chimerical, he must pa-
tiently add truth to truth, seizing it eagerly wherever found,
closing no  avenue of its approach, rejecting  no system or
theory as a whole, adopting  none,  conserving the truth of
all, and discarding the error wrapped  around with whatever
sage mantle of  antiquity, till  in the  grand symmetries of
nature, Science begins to display her own matchless beauties
and conditions.  This and this alone is the passport of every
man who would honor his profession and benefit his race.
  It seems  fitting, therefore, that in  the commencement of
this Course we should turn back for a brief review of the
prime  principles upon which all medical science rests.
  In medicine, as well as in all scientific research, chemistry
is at the true base.   Chemistry in its broadest sense may be
defined to be "that branch of natural science, whose object
is to investigate the  nature and properties of inorganic and
organized bodies, and to study the force by which  every
combination is made."
  The first object has been comparatively well  developed.
The laws which govern chemical action in its various forms
as manifest  in what are  known as the Ponderable elements
and their infinite combination, are well known and acknowl-
edged  as facts.   Chemists are well agreed as to the constitu-
tion of these bodies.   The Atomic Theory of Dalton is taken
as a basis, and on it  all our ideas of the composition of pon-
derable bodies rest.
  The  second object of chemistry, viz: "to study the force
by which every combination is made" has not been so sue- 
6
cessfully attained.  The almost insurmountable  difficulties
attending  the  investigation of imponderable  material, and
the tendency to  attribute  everything not readily explained
to some spiritual influence have almost prevented any suc-
cessful research.  The early investigations  or theories are
hardly worthy  of notice.  The laws of ponderable  matter
were so little'kuown that no aid could be gained analogically
from them, and the imagination was left unchecked in. its
wild and fanciful dreams.
   Gradually, however, as the laws of ponderable matter be-
came known and fixed, these theories yielded  to others hav-
ing a nearer approximate to the truth; till at length the laws
of the imponderables themselves were, to some extent, de-
veloped.   Electricity, under its various forms, of the voltaic
current, magnetism, electro-magnetism, magneto-electricity,
thermo-maguetism, heat, light, and certain  forms of attrac-
tion, were studied, and a multitude of facts collected, yet we
groped in utter darkness as to their real nature.
   Following these came Animal Magnetism, attributing cer-
tain unaccountable phenomena to a new  force, or the force
of magnetism modified by the living organism, especially
the human.  This soon led to Spiritualism, which included
certain phenomena  attributed to  some  spiritual influence.
The  doctrine  of Spiritualism of the present day is most
noticeable for  the rapidity of its spread  and the control it
exerts over the minds of its votaries.  Thousands to-day em-
ploy none but spirits, manifested through some medium, as
their physicians.  This condition  of things  challenges the
scientific  world  and especially the medical, to investigation.
In reply,  I am bold  to say, we are ready to meet the issue,
not, indeed, to enter into an examination of certain phenom-
ena, said  to occur under  such and such  circumstances, nor
to offer any explanation of said phenomena, but by  estab-
lishing the true laws of nature to expose the error of the
whole scheme.
   Investigations at the present proceed very differently from
those of former times.  Then science was an accumulation
of theories; now the interconnected chain  of established 
7
truths.  Then theories were continually rising or falling, as
here and there some fancy might strike some leading mind;
now each succeeding age and every philosophic mind brings
its contribution to the immutable structure of facts.  These
truths constitute the constantly-extending  base of further
research, and nothing can be accepted as truth which con-
travenes any of the already demonstrated laws  of nature.
Not only so, but it must render a satisfactory solution of
some phenomena hitherto unexplained. Thus and thus only
can it win its Way to the confidence of the scientific mind.
  For the past twenty years, many of our best  philosophic
minds have been examining the forces of nature; and  such
phenomena as  could be explained have been repeated, till
certain laws were established  from which  to  generalize.
The fog has not been lifted, but the  glimmer of day dawn
certainly appears.
  The subject of Correlation and Conservation of forces was
the first generalization suggested,  though uncertainly and
unsatisfactorily to any.  The subject was approached  from
different stand-points, until finally the conclusion was reached,
that " all the various forms of  imponderable material  were
convertible; that light was another form  of heat; that the
different kinds of electricity were simply owing to the differ-
ent manner of its production."  This doctrine soon included
life, or the vital  part of animal existence.
  In  1836-37, Dr. Samuel Jackson advanced the idea that
"Physiology might  be very properly designated as organic
physics."  In 1843 Mayer promulgated the same opinion.
  In  a course of lectures, in 1843, on this subject, I used the
following language : " There is an aether prevailing all crea-
tion which exhibits itself under the forms of electricity, gal-
vanism,  magnetism, light, caloric, &c.; and  though  elec-
tricity is not magnetism,  or caloric, or light, it is the same
fluid  under a different form.   So with  life or vital force, it is
one form of this aether, and exhibits itself differently as it acts on
animal, vegetable, or mineral substances."
  In  regard to ponderable material, the  following occurs:
" Among all the infinite variety of compound  substances, 
8
the  chemist reckons only fifty-five  elementary ones, and
these'they do not assert as absolutely simple, but call  them
so for convenience.  The probable truth is, that there is only
one  simple  ponderable substance."  But Mr. Grove,  of
London, published the first treatise upon this subject, and
in the edition of 1850 throws out the  conjecture that the
doctrine of correlation will apply  in physiology.
  A noticeable paper was read by Prof. Joseph Le Conte,
before the American Association  for the Advancement of
Science, at its meeting in 1859, at Springfield, from which I
quote the following:

  "Matter constantly changes its  form, but is itself i nde-
structible, except by  the same  power that  called it into
being.  The same quantity of matter exists in the universe
at all times.  So,  also, force  changes its form constantly,
but  is itself  indestructible, incapable of  increase or dimi-
nution, and  the same absolute amount of force  exists in
the  universe at all  times and forever.   The  mutual con-
vertibility of the various forms of force is 'correlation of
forces.'  The invariability of the  absolute  amount in the
midst  of constant change is called 'conservation of force.'
This principle of correlation and conservation of force  must
be looked upon as one  of the grandest generalizations in
modern science, a principle startling at first, but when clearly
understood and firmly grasped, almost axiomatic.  It  must
be considered a necessary truth, and as  such is a legitimate
basis of deductive reasoning."
  "The  correlation of plnjskal forces is universally recog-
nized as a principle in  science, and  not only so,  but has
already been productive of many beautiful and useful results;
but the correlation of physical and vital forces, while  gene-
rally recognized as a probable fact,  has only been speculated
on in a vague and as yet unfruitful manner.  The science of
life is scarcely yet ripe for the legitimate extension of this
principle over its domain."
  "There are four planes of material existence which may
be regarded as  being raised one above the other.  The first
and lowest is the plane of elementary existence, the  second
the plane of chemical compounds  or mineral kingdom, the
third the plane of vegetable existence, and the fourth the plane
of animal existence.   Now, it is apparently impossible for
any known force in nature to raise matter through all  these
grades at once.   On the  contrary, there  is a special  force 
9
adapted for the elevation of matter from each plane  to the
plane above.  It is the special function of chemical affinity
to raise matter from plane No. 1 to No. 2. All the changes,
too, which take place upon  plane No. 2 by the mutual reac-
tion of bodies situated on that plane, are under the guidance
and control of this force.  It is the special prerogative of the
force  of vegetation, of vegetable life, to lift matter from No.
2 to No. 3, i. e„ from the condition of mineral matter to the
higher condition of vegetable matter. All the changes which
take place upon this plane,  the laws which constitute vege-
table   physiology  are under  the guidance of this force.
Finally, the force  of animal life, and that alone, enjoys the
privileges of lifting matter still higher into the fourth plane,
i. e., the plaue of animal  existence.  No force can  lift from
No.  1 to No. 3, or from No. 2 to 4.   Plants  feed entirely
upon elementary matter, nor can animals feed upon mineral
matter.   *   *   Thus it seems  that after  matter  is raised
from  the elementary to the  mineral  condition, it requires an
additional force, of another and peculiar kind, to  raise it
into the vegetable kingdom, and again  another accession of
force  to raise it into the animal kingdom.  *    *   If, then,
it be  admitted  that  this is the relative position of these
planes—that it requires a greater and greater expenditure of
force  to maintain matter  upon each successive plane—then
it follows that any amount of matter  returning to a lower plane
by decoinposiliun must set free or derclope a force which may,
under favorable circumstances, raise other'matter from a lower to
a higher condition.
   "Again, in the same manner as  matter may be  arranged
in several distinct and graduated kingdoms, so it seems  to
me the forces of  nature may also  be divided  into distinct
groups arranged in a similar  manner, one above another.
These are the  physical, the chemical,  and  the vital  forces.
And  as iu the case of matter so also in the case of force, it
is impossible to pass directly from the lowest  to the highest
group without passing through the intermediate group."
  The broadest generalizations, however, yet  reached, were
published  by Professor  Joseph Henry, Secretary  of the
Smithsonian Institution  in 1857, in the Patent Office Agri-
cultural Report.  In an extended article upon Meteorology,
he speaks thus of the constitution of matter, p. 422 :
  "All the objects which are presented to us in the material
universe, and all the changes which we observe taking place
continually among them, whether those which immediately 
10
 surround us or those which we perceive at a distance either
 bv the naked eye or by means of a telescope, are referable
 to two principles—matter and force.  By the former we un-
 derstand the substratum of  that which affects our  senses,
 and by force that which produces the changes which we ob-
 serve in the former.   *  *  But  we cannot imagine a force
 without some bodily substance against which it is exerted ;
 the two ideas, therefore,  of matter and force, are coexistent
 in the mind, and on  a clear and definite conception of them
 depends that precise relation of the phenomena denominated
 Science.  Though the essence of force and matter may never
 be known to us, we can  study the laws  by which they are
 governed, and adopt such a constitution of matter as will
 enable  us to generalize  a vast number  of  facts.  *   *   *
 But such a generalization must be based on the well  estab-
 lished principles of the laws of force and motion, and be in
 strict accordance with accurately ascertained and properly
 estimated facts in the various branches of physical inquiry,
 in order that it may  be an exact expression of the apparent
 cause  of the phenomena, and that the  prediction from it
 may be true in measure as well as in mode.
   " In connection with the laws of the forces and motion of
 matter given above, we shall venture in this essay to express
 some of the widest generalization of the present day m the
 form  of what is called the Atomic  Theory.  *   *   *  *
 According to this theory  in its widest conception, ever}T por-
 tion of the  whole universe, or at least that part of it which
 is accessible to us by means of the telescope, is occupied by
 atoms  inconceivably minute, hard,  and  unchangable, sepa-
 rated from  each other by attraction  and repulsion.   This
 assemblage of atoms, constitutes the matter of the material
 universe, and the attractions and  repulsions, the  forces by
 which  they  are actuated, and to which is referable all the
 power  or energy which produces the changes to which mat-
 ter is subjected.
  " These atoms, thus endowed, form a plenum  throughout
 all space constituting what is called the etherial  medium,
 and in  it, at wide intervals from  each  other, are 'isolated
 masses  of grosser matter which constiute  our world, the
 planets, the  sun,  and  the stars.  These also consist of atoms
 of another order, or groups of atoms  with spaces between
 them  wide in comparison with the size  of  the atoms, and
these spaces pervaded by the minuter atoms  of the ethereal
medium  * * According  to this theory the various isolated
 bodies of the universe act upon each other by means of the 
11
force of gravitation, and also by tremors  and vibrations in
this medium, radiating in every direction from each body
as a center.   *   *  *
   " AVe  are  obliged  to assign to the ethdreal medium a
similar  constitution to that possessed  by grosser matter,
viz.: that it  consists of inert atoms at great distances from
each other relative to their own size, and each kept in posi-
tion by attracting and repelling forces.   Through this me-
dium impulses  or minute agitations are transmitted in celes-
tial space from  planet to planet, and from system to system,
and these tremors or waves  constitute light, heat, and other
emanations  which  we receive  from the sun ;  or, in other
words, the solar emanations are not matter but motion com-
municated from  atom to atom, beginning at the luminous
body and diffused in widening  spherical surfaces, enlarging
in size and diminishing in intensity, to the farthest portion
of conceivable  space.  *  *  *
   " The phenomena of light, of heat, of the chemical and
phosphorogenic emanations, have all been referred to vibra-
tions of the ethereal  medium, and all the facts which have
thus far been observed are in accordance with this generali-
zation.   The question, however, naturally arises as to what
explanation we can give of the multiplied and various phe-
nomena which  are constantly presenting themselves to us in
connection with all changes which are taking place around
us in Nature, or which exhibit themselves  to  the chemist
and pliynicist in their investigations of the minuter reactions
which  are brought about by their agency, and which  are
classed  under  the  general  term of electricity.   *   *   *
Now these phenomena may be referred  to an accumula-
tion of the ethereal medium in one  portion of space, and
corresponding  diminution in the adjacent space around.   If
the particles  of the ethereal medium, when  thus accumu-
lated, act  at  a  distance on other portions of the  same me-
dium, we shall  have a rational exposition of the phenomena
of statical electricity; and in the restoration of the equilib-
rium of. the medium, or in its return to its natural condition,
we have a plausible cause of the dynamic effects belonging
to the same class.   *  *   *
   " But what is this vital principle which thus transcends
the sa^-o^v of  the chemist and produces groups of atoms
of a4l^^^fxity far exceeding his present skill ?  It is gen-
erally kiiwii under the name of the 'vital force;' but since
the compounds which are produced under its influence  are
subject to the same laws, though differing in complexity, as 
12
those produced by the ordinary chemical forces; and since
in passing from an unstable  to a more stable condition in
the form of smaller groups, they exhibit, as will be rendered
highly probable hereafter, an energy just equivalent to  the
power exerted by the sunbeam, under whose influence they
are produced, it is more rational to suppose that they are
the result of ordinary chemical forces  acting under the di-
rection of what we prefer to call the vital principle.
  "The general conclusion  which  has been arrived at is,
that all  the different  physical  energies, whether that which
is called chemical action, heat, light, electricity, magnetism,
or muscular motion,  or mechanical power, are all  referred
to the disturbance of the equilibrium of the atoms, and its
subsequent restoration due to their attractions  and repul-
sions; and that all these forms of energy are in one sense,
as it were, convertible into each  other; or, in other words,
the force generated in the restoration of the equilibrium in
one case is sufficient to disturb it, though in different form,
perhaps, in another."

  I now propose to extend these generalizations by classing
the "ethereal medium" as a constituent element, subject to
all the laws that are commonly resticted to gross matter.
  In 1843 I  advanced a similar theory, and taught it in  the
lecture  room for the  following years.   The  theory as pro-
posed was expressed in the following laws :

  "1. All created substances exist under two forms, ponder-
able and imponderable.
  "2.  A  definite amount of ponderable  substance .was
created  at the beginning, and  has been neither increased or
diminished.
  "3.  A  definite amount of  imponderable  substance was
created  at the beginning and has  been neither increased or
diminished.
  "4. All the forms of ponderable matter are but the aggre-
gation of  elemental ponderable atoms,  connected with vary-
ing  quantities  of imponderable material,  under  different
circumstances and relations.
   "5. All the forms  of imponderable substance,  are but the
various  manifestations  of elemental imponderable atoms,
under different circumstances and relations. 
13
 " 6. Imponderable substance in definite quantity, must form
an elemental constituent of every ponderable body."
  It will be readily perceived that the first five of these laws,
entirely correspond with the theory enunciated by Professor
Henry in 1857, and that, in  addition the "atomic theory of
Dalton," is  extended to cover  the  imponderable as well aa
ponderable  material, or, in other words, it extends  over all
the matter  which falls within  our cognizance,  ethereal as
well as gross.
  For the sake of convenience  I have  called ponderable or
gross  matter, Materia, and the  imponderable  or  ethereal
medium, ^Etheria, abbreviating them Ma. and Aa.   I shall
not at this time further refer to the first five of  these laws,
as Physicists accord to them the high rank of well established
principles.
  The sixth invites our attention.
  If it be true, that ^Etheria enters into every compound as
a constituent, then it is apparent that what we have  hitherto
regarded as analyses, are so, in  fact, but in part.  One  essen-
tial has been overlooked, and the whole formulary of Chem-
istry has to be recast.
  In the article previously referred to as containing the latest
generalizations, we have the idea of atoms, but nowhere, the
notion that these atoms of JEtheria, are  subject like  those of
Materia  to. the laws laid down  by the Atomic  Theory.  I
propose  in  law 6, to extend the entire Atomic  Theory to
yEtheria, thus recognizing it as a  constituent  element of
matter in its general sense.
  We are thus brought to the consideration of the grounds
on which this more extended  generalization is  believed to
rest.
  There are certain  phenomena exhibited by  many sub-
stances, simple as well as compound, that have ever perplexed
the Chemist, the exposition of which is, by  this  law  made
satisfactory.  Not less effective will the physiologist and the
pathologist, find  it in  solving a multitude  of phenomena
hitherto  enveloped in mystery.
  A class  of phenomena,   quite  general,  called  Change 
14
of Form in bodies, illustrates precisely the part this new ele-
ment plays in chemical composition.  Ice, a dense, brittle,
vitreous substance, when heat is applied, bringing its tem-
perature to  32°  F.,  remains stationary  till  140° to  every
pound has disappeared, when it changes its form  and be-
comes liquid, losing  most of its original  properties and as-
suming others.  It is said that this 140° of heat becomes
latent.  Now what is the meaning  of this explanation, if
explanation it  be?  Where is this 140° of caloric?  To say
that it is latent, is to  say it has vanished, i. e. to say nothing.
  Heat is  simply the  particles of setheria in a state of intense
vibration; and when  the heat becomes latent, or  disappears,
or at least so  that its vibrations are not  detectable by the
thermometer, the simple question is, what  has  become of
these vibrating particles of setheria ?  The same  cause that
commenced  the vibration still continues,  aud yet the vibra-
tion has ceased!  Are there any indications that point to
what is taking place?  The same law that gives us the solu-
tion to all established chemical changes, if applied, will give
a solution here  also.  Why not then apply it?  Oxygen
brought into contact with certain substances disappears—i. e.
becomes latent—can no longer be found, and  we  say it has
combined to form a  new substance.  Here heat has disap-
peared, and  a  new substance is formed; why not carry out
the analogy of its having entered into combination, as well
as oxygen ?
  Again,  let the heat be  continued and the temperature
rises with uniformity, until the point of 212° F. is reached,
when a second absorption takes place, and  1008°  F. to  every
pound of water, vanish.  As before, these particles of setheria
having entered into  actual combination  with the water to
form a new substance, can  no longer vibrate, and of course
cannot effect the thermometer.  Ice, water, and steam, there-
fore, form a series of bodies, whose general formulae is H. O.
Aax., in  which  x varies  as  the number of equivalents of
setheria vary.  If we reverse the process, and  reduce the
steam to  water, the  element setheria as  soon as liberated,
resumes its vibrations, and  exposes its presence as heat. 
15
  This condition is general.  A chemical building up absorbs
surrounding vibrating particles of setheria as an element of
the new compound, and whenever this runs down, setheria
is liberated, and through some manifestation exposes is pres-
ence.  The law, therefore, that all the physical properties
of a body depend upon its chemical constitution, appears to
be true in its  broadest application.  Water, ice, and  steam
are as much different compounds as the atmosphere, laughing
gas, and aqua fortis.
  A class  of phenomena, called Allotropism,  to which no
satisfactory exposition has  been given, is  very closely allied
to the above.   Indeed, there is no good reason known why
water may not be called an  allotropic condition of ice.  The
phenomena are so closely  related that it  is  not  easy to
say wherein the  difference consists.  Ice,  without  any
additional  element, changes its properties;  in the same
manner  sulphur, without any additional element, changes
its properties.  In one case it is called " allotropism," and
in the other " a change of form."  Perhaps  we shall be able
to understand better the difference if we translate the Greek
word  Allotropism.   It  means  to change to another.   The
difference  may be that the one class of phenomena  is a
common occurrence, while the  other is confined to the lab-
oratory.  The only real difference is  that in one case the
change of form takes place in compound  bodies, and the
allotropic condition in elementary or simple bodies.
   Among the  elementary  bodies are chlorine,  phosphorus,
sulphur,   &c,  that  under  certain   conditions,  without
the addition  of any Materia whatever,  assume entirely
different properties,  to such  an  extent as to lose  their
identity.  They  are then said to  be  in an "allotropic
condition," oxygen becomes ozone, sulpher loses its prop-
erties and becomes  more  like  gutta percha,  phosphorus
is no longer identified, chlorine assumes new properties,  &c.
It is a fact worthy of notice in  regard to these remarkable
changes, that no elementary body assumes its allotropic form, without
being exposed to Mtheria, either in a condensedform, or in an intensely
vibrating or disturbed state.  It is equally true  that no compound 
16
body assumes its change of form without being exposed to Mhena,
either in a condensed form or in an intensely vibrating or disturbed
state.  Both results are produced under the same law, and origi-
nate from the same cause.   Thus Allotropism is readily ex-
plained by the addition or diminution of setheria as an ele-
mental constituent of the body.   In the case of Ozone there
are cogent reasons for believing that its production is caused
by depriving Oxygen of one or more equivalents of setheria.
It may be, however, that setheria has been added.
  Another subject inviting  our attention  is Isomerism—an
anomalous condition of certain substances, seeming to stand
in the  face of this prime law of chemistry, that difference of
properties is due to a difference of composition.  Many sub-
stances are found of very essentially diverse  qualities,  which
upon analysis, disclose precisely uniform elements and uni-
form proportions.   Liebig finds  that the  essential oils of
juniper,  rosemary, turpentine,  copaiba, and the  essence of
lemon  constitute  such a class.  Much as these substances
differ in taste, odor, medicinal qualities, boiling  point, and
specific gravity, they are entirely uniform in elements  and
proportions.
  It  is  to  be  noticed  in  reference   to  these  bodies
that they are of unstable composition, and  the  atoms can
sometimes be made to change their position by an impulse
from without, or  by the adition of heat, and then combine
again,  forming other substances having  entirely different
properties.
  It is generally laid down  in articles upon Isomerism that
"these remarkable facts can only be accounted  for by the
different groupings  of the  atoms;" that is, whilst all the
various bodies have only the same elements out of which to
construct, it  is  supposed that each has its own peculiar
method of arrangement, by which is thus produced results
of such widely different characteristics.  The grounds  of this
supposition are  not any known  facts that  there is such a
peculiarity  of groupings,  nor any  analogies elsewhere in
chemistry, in truth  the  analogies are uniformly against it,
but simply  that it affords an explanation  to  what has been
hitherto regarded as otherwise unexplainable. 
17
  But are these phenomena o4^yise unexplainable?  Have
we not already found the element wanting to show the real
point of  difference ?  Now are there any indications that
setheria is the varying element in  these similarly constituted
substances?  It is worthy  of note that among the specific
points of difference, besides the odor,  medicinal effects, &c,
was  the  boiling point, thus clearly indicating some essential con-
stitutional difference in the amount of cetheria.  Thus, then, these
bodies instead of being Isomeric, having  a uniform consti-
tution of Cn. Hp. appear to revert back to the general con-
dition of all chemical combinations,  and have the general
formula  of Cn. Hp.  Aax, in which x  varies as the number
of equivalents of setheria vary, and  the law that physical
properties depend upon chemical composition, holds good.
  We are therefore necessitated to choose between these two
conclusions—to set  aside a  well established law of chemical
condition, and adopt a hypothesis without warrant of fact and
against analogy,  or  to make the Atomic Theory universal'
over the imponderable alike with the ponderable  material,
thus affording a full and satisfactory exposition of Isomer-
ism, restoring  the law of  chemical condition, and making
science harmonious.
  It is pertinent  to say that the introduction of a new con-
stituent element, ^Etheriain all chemicalanalysis will modify
methods of  research, and  give precision  to many hitherto
unsatisfactory investigations.  It opens a wide field for the
modern chemist, and promises laurels for his brow.  As im-
portant as  this may  be to the Chemist, it  is scarcely less  so
to the Physiologist and  the Pathologist.  Bearing in mind
that the addition of this  new element to already existing
compounds, does not destroy but modify existing  laws, it is
important to inquire what laws of living organisms depend
upon the new element, setheria.  The science of life or vital
force is ripe for speculation and theory but not for scientific in-
vestigation.  When the laws dependent on the new element
eetheria are fully developed in the inorganic world, when
understood  in vegetable  organizations, then it will be time
to push our  inquiries  to this more  subtle  material of the
most complex living organism. 
IS
   Without going, at the present time, into the exposition of
 vital force, we may be enabled to explain certain physiolog-
 ical and pathological phenomena more satisfactorily by this
 new generalization, than by any other existing law.
   The production of " animal heat" has given rise to various
 theories and speculations, none of which have proved satis-
 factory.   The  most correct generalizations on this subject
 are  that the greater portion  of material consumed  by man,
 about a  ton and a half each year, is ox}rgenized or burnt, /. e.
 from a  highly  organized,  unstable  condition, it  has been
 degraded to an unorganized and more stable form;  and that
 during this process which takes place in every portion of the
 system, heat is evolved, /, c. hidden or latent heat has become
 tangible heat.
   Without knowing the precise uature of heat, this langua.o-e
 is far from being definite, in fact, contains no idea of the
 process  it attempts to elucidate.  This  indefiniteness and
 'uncertainty disappears the moment we  introduce setheria as
 a constituent element, and the whole process is clear to the
 mind.  In the scale of existence, materia  is elevated with
 every accession of setheria as  a constituent element till  it
 passes from the mineral to the vegetable, and finally reaches
 the  highest and most delicate organism in man.   Heat, as
 before stated, is simply a-theria  in a state of intense vibra-
 tion.  The moment these  atoms combine with any form of
 materia, their vibrations cease, and, of  course, the heat dis-
 appears, nor can the vibrations again commence as long as
 this compound remains intact, but the  moment it is broken
 up from  any  cause, setheria is  liberated in an intensely-
 vibrating condition, which constitutes heat.
  We therefore receive setheria into the system in  the food,
 in a quiescent, combined state, as  an elemental  constituent
 of the food; but as assimilation or nutrition takes place this
 food is broken up, a small  part  being used to build up the
 system, but by  far  the  larger portion  is eliminated in  its
 more stable form, as carbonic  acid, water, &c, thus libera-
ting setheria in  every point of  the  system in its intensely
 vibrating condition, or in other words as heat. 
19
  These generalizations are no less interesting to the Pathol-
ogist.  All inffamation originates in an excess  of heat—its
other characteristics follow.  From what has been said, it
will  readily be perceived that this  heat must come from an
abnormal degradation of some  tissue as the prime cause.
No provision being made to remove this vibrating element,
a diseased condition follows.
  The application of cold water to gunshot wounds disposes
of the excess of heat caused by the degrading process in the
region of the injured part.
  In general terms, if this generalization  be true, inffama-
tion, in whatever of its multitudinous forms it appears,  can
only be subdued  by arresting the  degrading  process at the
seat  of the disease.
  Illustrations of the application of these generalizations
might be  multiplied to an indefinite extent, but I designed
only to revert to some of the prime principles on which  our
profession rests, that you, gentlemen, in the prosecution of
your studies and research, may extend the domain of known
truth, honor your profession, and benefit mankind.