OZONE AND ANTOZONE. 
BY CHARLES M. WETHERILL, PH. D., M. D. 
Schoex bein, in the year 1840, called attention to the existence of a substance 
which he named from one of-its most striking characteristics, ozone, (o£(v, I 
smell.) The peculiar odor in the neighborhood of a good electrical machine 
when in action, and especially when the electricity issues from a point upon 
the prime conductor, or is drawn from it as a spark, had been well known. 
A similar odor had also been perceived accompanying the fall of the thunderbolt* 
This phenomenon had been characterized as a phosphoric or a sulphur smell. 
Schoenbein called attention to the fact that a similar smell is perceived during 
the decomposition of water by the voltaic pile, and is observed accompanying 
the oxygen which appears at the positive pole when the gases are collected 
separately, and that it is also experienced in many chemical processes, espe- 
cially in those involving a slow combustion. In explaining the odor of the 
active electrical machine, it had been assumed that the sensation is due solely 
to a peculiar action of the electricity upon the organs of smell, and not to the 
presence of a material substance; but Schoenbein discovered, in the cases 
alluded to, the existence of a body having the chemical properties of active 
oxygen-that is, of this gas in its condition of entering most readily into chemi- 
cal combination, to which he attributed the phenomenon in question, and to 
which he assigned a characteristic name. 
During the twenty-five years which have elapsed since Schoenbein's dis- 
covery, this difficult subject has been investigated by many scientists, and 
especially by Schoenbein himself, by Marignac, De la Rive, Fremy, Erdmann, 
Berzelius, Williamson, Becquerel, Baumert, and others equally well known in 
research. While there are few subjects which present a wider field for investi- 
gation, or which are more important in their relations to a knowledge of animal 
life, and to some interesting practical questions in technology, there are few which 
require a greater patience, or a greater degree of skill in manipulation for their 
research. It is in consequence of these difficulties that our knowledge of 
ozone is so limited, notwithstanding the time and labor which have been be- 
stowed upon it. It is the object of the present article to give a brief sketch 
of what is known-respecting this substance, on the authority of the article ozone 
in Poggendorff's Dictionary, and from the essays of experimentors in various 
scientific periodicals. 
Some time elapsed after its discovery before very definite views were held 
as to the true nature of ozone. Schoenbein, who for a long time denied 
that ozone is. an allotropic form of oxygen, at first supposed that it was 
a new body which, in union with oxygen, or perhaps with hydrogen, con- 
stituted nitrogen, to which he attributed a compound character. De la Rive 
imagined that the peculiar smell was due to the action upon the organ, of 
* Homer notices the smell of the thunderbolt. Mohr in Pogg. Ann., xci, 625. Thus, in 
the Odyssey, book xii, verse 417, and xiv, 307, Jupiter strikes a ship with a thunderbolt, 
ev de Pestov Trfyro, "quite full of sulphurous odor." In the Illiad, viii, 135, Jove hurls a 
bolt, " with the flame of the burning sulphur," into the ground before Diomede's chariot. 
In the same poem, xiv, 415, Ajax hurls a rock at Hector, who falls " like a mountain oak 
struck by lightning, which lies uprooted, and from which the fearful smell (od^) of smoking 
sulphur rises." OZONE AND ANTOZONE. 
167 
very finely divided metallic dust of platinum, or of gold, which was separated 
from the conductors by the electric current, and converted into oxides of the 
metals ; but Schoenbein proved this explanation to be untenable by the experi- 
ment of employing hot points for the issuing of the electric charge into the air. 
Under such circumstances the hypothetical separation of metallic particles and 
their oxidation should be increased; but, upon the contrary, there was no 
smell of ozone at all perceptible. Besides this, ozonized air, when shaken in 
a bottle with water, does not lose its peculiar smell. Hence it is a gas, not 
absorbable by water, but altered in its character by heat. Marignac and De 
la Rive subsequently performed experiments which seemed to show that ozone 
is pure oxygen. As Marignac was unable tj obtain ozone by electricity with 
oxygen unless jnoistiire was present, it was possible that the substance might 
be peroxide of hydrogen, and this hypothesis became highly probable by the 
extended and careful research upon this point by Dr. Williamson. This chem- 
ist prepared ozone by the electrolysis of sulphate of copper, dried it by passage 
over chloride of calcium, and passed it through a tube containing copper turn- 
ings, boated to redness, which had been fifst oxidized and then reduced in a 
current of carbonic oxide. By the experiment, oxide of copper and water 
resulted. .Schoenbein now adopted this hypothesis, having been fortified 
by experiments of his own. At first he regarded ozone as a higher oxide 
(HO3) than Thcnard's peroxide (IIO2) of hydrogen; but at last retained the 
latter formula. Schoenbein defended this view pertinaciously, supporting it 
by experiments and by arguments against that of De la Rive, Marignac, Mar- 
chand, Erdmann, Berzelius, Fremy, and Becquerel, who prepared ozone with 
pure oxygen, (obtained from chlorate of potassa, the gas being washed and per- 
fectly dried,) either by the electrical machine or by an induction current. Ma- 
rignac, by acting with ozone upon pure powder of metallic silver, obtained 
nothing but the peroxide of that metal. Hence the conclusion was warranted 
that ozone is oxygen in an allotropic form. Schoenbein's opinion was based 
upon his view of the halogen bodies, which, like Berthollet, he believed to be 
peroxides of unknown radicals, and from the analogy of ozone, in its chemical 
behavior, to chlorine. He also assumed that no element is known which has 
an action upon the olfactory nerves to call forth the sensation of smell; chlo- 
rine, iodine, and bromine being, as he believes, compounds, while phosphorus 
and arsenic act upon this sense by reason of their passage into the condition 
of oxides. 
Baumert contended that the odorous gas evolved by electrolytic action is 
essentially different from ozone obtained by the electric spark. Its constitution, 
according to this chemist, is HO3; it yields no water to anhydrous phosphoric acid 
until it has first passed through a tube heated to redness, which he supposed 
decomposes the IIO3. Baumert, however, in subsequent experiments, acceded 
to the opinion (derived from their investigations) of De la Rive, Erdmann, 
Marignac, Marchand, Fremy, and Becquerel, that ozone is an allotropic condi- 
tion of oxygen. 
Schoenbein, in 1858, discovered that if to diluted peroxide of hydrogen a 
few drops of solution of acetate of lead be added, or that if ozonized oil of tur- 
pentine be shaken with the same lead salt, peroxide of lead is formed. The 
same reaction takes place when ozonized oxygen acts upon basic acetate of lead. 
When the peroxide of lead thus formed remains in contact with the peroxide 
of hydrogen, both are reduced; the result being water, protoxide of lead, and 
oxygen. From this reaction, Schoenbein assumed that the oxygen in the perox- 
ides of hydrogen and of lead exists in an opposite condition of polarity, thus: 
"F - 
HOO and PbOO, and that by'the union of these molecules of oxygen the ordi- 
nary inactive oxygen results. Clausius and De la Rive also imagined a simi- 
lar molecular condition for oxygen. 168 
OZONE AND ANTOZONE. 
Schoenbeia designated those bodies containing negatively active oxygen, 
(orO), ozonides; such are permanganic (M112O2O5) and chromic acids (Cr2O3O3), 
and the peroxides of manganese, (Mn 0,0), silver, (Ag 0,0), and lead, (Ph 0,0). 
He named antozonides; peroxides of hydrogen, (HOO), barium, (Ba 00), and 
all bodies which contain oxygen in a positively active condition, (0), and this 
form of oxygen he called antozone. 
• • • • 
This chemist succeeded in obtaining antozone (0) by projecting finely pow- 
+ 
dered peroxide of barium (Ba 00) into cold monohydrated sulphuric acid. A 
gas is evolved which both Houzeau and. Schoenbein formerly supposed to be 
ozone, but which has different properties. It blues iodide of potassium starch 
paper, and smells somewhat like ozone; but when agitated with a little water 
it loses its odor completely, and forms peroxide of hydrogen, which reaction 
ozone does not produce. A slip of filter-paper saturated with a mixture of 
dilute solution of ferricyanide of potassium and a persalt of iron is speedily 
turned blue in antozone gas, but in ozone behaves as in atmospheric air. A 
very small portion of the gas evolved by this reaction in antozone. This is 
due to the elevation of temperature, which transforms the antozone into ordi- 
nary oxygen. 
Another means of distinguishing ozone from antozone consists in a'slip of 
paper imbued with solution of sulphate of protoxide of manganese, which 
speedily becomes brown in ozone, from the formation of peroxide of manga- 
nese. In antozone, not only does this reaction not take place, but papers 
browned by ozone are bleached by antozone. 
A distinguishing test may also be found in the behavior of the two gases 
with permaganic acid, which antozone decolorizes and ozone browns. 
Dr. Gr. Meissner discovered that, if well dried electrified air be passed through 
water, (which may or may not contain air,) it forms, upon issuing into the at- 
mosphere, a more or less dense cloud or mist. The same phenomenon takes place 
when electrified air issues into a moist atmosphere. 
This cloud is formed by the electrifying of either pure oxygen or of air; but 
not by pure hydrogen, or nitrogen. It occurs, whether the gas contains ozone 
or not, but in the latter case to a less degree. 
By contact with drying substances, as concentrated sulphuric acid, chloride 
of calcium, and even concentrated solutions of certain salts, the mist may be 
caused to disappear ; but it forms again by the addition of aqueous vapor. 
The air left to itself gradually loses this mist-producing property, and if the 
antozone cloud be confined, the water is, after a while, precipitated upon the 
sides of the vessel, and can no more be produced by the action of vapor, unless 
the air be electrified again. 
Ozoniferous moist air retains its cloud-compelling property longer than that 
which does not contain ozone; and, on the other hand, dry ozonized air pre- 
serves this property still longer. Meissner satisfied himself, by numerous ex- 
periments, that this phenomenon of mist is due to antozone, and that electrified 
air contains both ozone and antozone, the former element being absorbed, and 
the latter not absorbable by iodide of potassium, or pyrogallic acid. He dis- 
covered, also, that antozone prepared by electricity is identical with that obtained 
by the decomposition of peroxide of barium, as the former, when brought fresh 
and dry in contact with water, generates a proportion of peroxide of hydrogen. 
Meissner regards peroxide of hydrogen as a chemical compound of antozone 
and water ; but cloud or mist as a physical aggregate of antozone and vapor 
of water, in which the chemical affinity of the two bodies is very much weak- 
ened. Von Babo supposes the antozone cloud to be in most cases peroxide of OZONE AND ANTOZONE. 
169 
hydrogen, and that it may be formed b'y the action of ozone also; its disap- 
pearance he explains by the gradual precipitation, or decomposition of the 
peroxide. 
Meissner regards the formation of ozone and antozone possible simultane- 
ously by the action of either positive or negative electricity upon ordinary 
oxygen; but Von Babo believes that only ozone is formed by the current. The 
latter chemist found that ozonized air experienced no diminution of ozone upon 
its passage through a solution of permanganic acid, but that this took place 
immediately if the air came first in contact with substances capable of forming 
peroxide of hydrogen; also, that ozonized oxygen, free from nitrogen, gen- 
erated with water neither cloud nor peroxide of hydrogen. 
According to Meissner, antozone is formed by all processes of oxidation and 
combustion in oxygen; and, since the ozone enters chiefly, during combustion, 
into the oxide thus generated, that the result is principally antozone (or peroxide 
of hydrogen) in the free state. Antozone is, therefore, according to Meissner, 
the cause of the cloud in tobacco smoke, the smoke of chimneys, of gunpowder, 
fogs, and aerial clouds. Meissner found that the fumes of phosphorus in the 
air are antozone clouds, and not nitrate of ammonia, the greater portion of the 
ozone generated by the reaction being absorbed by the phosphorus. 
Meissner discovered that air saturated with moisture gives a cloud, upon sud- 
den rarefaction, until the barometric pressure is reduced to eight inches. This 
corresponds to an elevation of 27,000 feet. By the observations of Kamtz, the 
average altitude of the lightest and highest clouds, the cirrhi, is 20,000 feet, 
and their greatest height 24,000 feet. 
According to Meissner, water condensed from air or oxygen has the form of 
vesicles, while, when it is separated from other gases, the moisture condenses 
in the form of rain or solid drops. 
A most curious occurrence of antozone presents itself in the fluor spar of 
Wolsendorf, in Bavaria. This mineral has a peculiar smell, due to antozone, 
which Schoenbein found in the proportion of of the weight of the spar, 
because five grammes, when rubbed with water, yielded 2.125 milligrammes of 
peroxide of hydrogen. Since antozone is contained in powder-smoke, it may 
be surmised that the copious rains which follow great battles are due, in a mea- 
sure, to this body, the decomposition of the cloud of antozone-water being either 
a cause or an effect of the electrical excitement in the atmosphere. 
Having prepared antozone from an antozonide, Schoenbein sought to obtain 
ozone from an ozonide, and selected permanganate of potassa for that purpose. 
Bertazzi had already (Cimento ii, 291) shown that by the action of dilute 
sulphuric acid, at a low temperature, upon this salt, a gas was generated which 
had the properties of ozone. Schoenbein, upon a further investigation of the 
subject, found that peroxide of barium projected into the olive-green solution of 
permanganate of potassa, and oil of vitriol, of 1.85 specific gravity, evolves a gas 
which has the smell and chemical properties of ozone. It acts strongly upon 
the mucous membrane, polarizes platinum negatively with great power, and 
destroys organic coloring matter and pyrogallic acid at the ordinary temperature. 
B. Boettger, in calling attention to this experiment, states that he had two 
years previously described the effect of oil of vitriol and permanganate of po- 
tassa in producing a long-continued evolution of ozone. He considers the addi- 
tion of peroxide of barium superfluous, and, for the development of ozone, 
adds two parts of dry powdered permanganate of potassa to three of hydrate 
of sulphuric acid in a bottle. By this reaction a strong ozone smell is at once 
perceived, and all of the characters of the gas may be established by the proper 
reagents. 
Schoenbein has determined that antozone has a density less than hydrogen, 
and that it liauefies at a pressure of 150 atmospheres. Ozone and antozone. 170 
OZONE AND ANTOZONE. 
exposed to the dark rays of the spectrum, unite, with explosion, and yield 
ordinary oxygen. 
Schoenbein considers that oxygen undergoes chemical polarization in the 
body when respired, and accounts thus for the rapid changes which take place 
in the tissues. He has found peroxide of hydrogen in the urine, and has dis- 
covered that the blood corpuscules instantly decompose this compound. He 
has given the following test for the peroxide of hydrogen. To water, supposed 
to contain the peroxide, he adds one or two drops of a solution of a salt of 
bismuth, nickel, cobalt, thallium, &c., and then just enough of potassa to pre- 
cipitate the hydrated oxide of the metal. He then adds a little iodide of po- 
tassium and starch, and lastly one or two drops of acetic or dilute sulphuric 
acid. If the merest trace of peroxide of hydrogen be present, the liquid is 
instantly colored blue. 
The following is Schoenbein's method of determining quantitatively the de- 
composition of oxygen into ozone and antozone. During the slow oxidation 
of metals, according to this chemist, the oxygen is chemically polarized; one 
of its atoms (ozone) unites with the metal or oxidizable matter, while the other 
atom (antozone) combines with water to form peroxide of hydrogen. Schoen- 
bein agitates an amalgam containing five per cent, of lead, with very dilute 
sulphuric acid of known strength, in a large bottle partially filled with air or 
oxygen. After a few moments of agitation, a quantity of sulphate of lead is 
produced, and peroxide of hydrogen is found in the acidulated water. He 
ascertains the oxygen which has combined with the lead, by determining the 
amount of uncombined acid, thus calculating the sulphate of lead formed, and 
consequently its oxygen. He determines the peroxide of hydrogen in another 
portion of the water by a standard solution of permanganate of potassa, and 
finds' the quantity of oxygen in this peroxide to be very nearly the same as 
that contained in the oxide of lead. 
Different chemists have determined the diminution of volume experienced by 
air or oxygen during ozonization. 
Andrews and Tait placed pure dry oxygen in a tube and discharged elec- 
triuty through the gas. With still discharges a diminution took place, which 
wm at first rapid and then slow until a maximum was reached, yielding a 
diminution equal to of the original volume. When, now, a few sparks were 
passed through the gas it expanded of the former diminution, but did not 
attain its original volume. With rapid or spark discharges, oxygen experiences 
a diminution of volume, although less than by still discharges. Oxygen, con- 
tracted by the formation of ozone, when left to itself at the ordinary tempera- 
ture, expands again gradually. At 100° Centigrade it expands more rapidly, 
and at 270° it regains its original volume and loses all of the characteristics of 
ozone. At this temperature, therefore, ozone is destroyed. Andrews and 
Tait found that, by still discharges, oxygen cannot lose more than of its 
volume, unless the ozone be removed as fast as it is generated, in which case 
the diminution may proceed indefinitely. They determined 60 for the density 
of ozone compared with oxygen, which makes it six times lighter than lithium. 
They were unable to condense it to a liquid at ordinary pressures by a freezing 
mixture of solid carbonic acid and ether. 
Ozone may be prepared for examination most readily by dropping, in small 
quantities, dry permanganate of potassa in a bottle containing a little oil of 
vitriol, or by placing a stick of phosphorus, scraped clean under water, in 
the bottom of a capacious vessel containing enough lukewarm water to half 
submerge the phosphorus. In either of these cases a slip of iodide of potas- 
sium starch-paper becomes instantly blue when immersed in the air of the ves- 
sel, and the different ozone reactions may be readily perceived by employing 
the appropriate tests. The gas may also be investigated with the above starch- 
paper in the neighborhood of a point upon the prime conductor of an elec- OZONE AND ANTOZONE 
171 
trical machine, from which still discharges are issuing. It may he obtained by 
the inductive current of the Ruhmkorff coil, or by the electrolysis of water, 
using a powerful Bunsen or Grove battery, and employing gold or platina for 
the positive electrode, from which proceeds a current of oxygen, laden with 
ozone. The hydrogen gas, issuing from the negative electrode, possesses no 
odor of ozone, but this smell is perceived when the two gases are collected 
together. The antozone, formed here by the polarization of the oxygen, unites 
with the water to peroxide of hydrogen. If the water thus electrolized con- 
tain substances capable of union with oxygen, as hydrochloric, hydriodic acids, 
and their salts, also sulphurous acid, sulphuretted hydrogen, coal, iron filings, 
&c., or if the liquid or electrodes be heated, no ozone smell is perceived. 
There is no process for obtaining pure and isolated ozone, although a con- 
stant current of air laden with this gas may be procured for a certain time by 
the action of sulphuric acid upon permanganate of potassa, or by passing 
moist air through a tube containing pure phosphorus, and washing the gas with 
water. The generation of ozone by the electric discharge is so slow that Bau- 
mert, by passing 500,000 sparks in an hour, obtained only enough of this gas 
to liberate one milligramme of iodine from its potassium salt. 
Circumstances influence the production of ozone by the electrical discharge. 
Under the same conditions, sparks of 25 millimetres in length generate twice 
as much ozone as sparks of 4 to 5 millimetres long. 
Employing hermetically sealed tubes of millimetres diameter and 70 mil- 
limetres long, § of the oxygen can be converted into ozone; but by continuing 
the discharges the ozone diminishes, so that in 24 hours it equals only of the 
original oxygen. 
By the electrolysis of water, containing of sulphuric acid, Baumert ob- 
tained only one milligramme of ozone in 150 litres of the mixed gases; but 
when the water contained chromic acid instead of sulphuric, he found the same 
quantity of ozone in 10 litres of the mixed gases. 
Ozone is generated by means of phosphorus only in a moist air, containing 
oxygen ata medium temperature. When the atmosphere is deprived gradually 
of its oxygen, by means of ignited oxide of copper, the production of ozone 
diminishes, and ceases entirely when there is no longer any oxygen present. 
Ozone is not formed in pure carbonic acid or hydrogen gases. With 1 
volume of oxygen and 4 of carbonic acid, the formation of ozone is easy. In 
an explosive mixture of hydrogen and oxygen, the generation of ozone is pow- 
erful; the phosphorus shines vividly, and can acquire heat sufficient to kindle 
and explode the mixtqre of gases. In pure oxygen, at the ordinary pressure 
of the atmosphere, phosphorus, by the presence of water, does not produce 
ozone until the temperature is raised from 75.2° to 86° Fahrenheit. At this 
temperature the phosphorus begins to emit light, and the illumination and 
ozone generation arc powerful at 96.8° Fahrenheit. 
Oxygen expanded to four timesits volume, by the air-pump, yields ozone, by 
phosphorus, at the ordinary temperature; but at 32° Fahrenheit there is no 
production of ozone. In dry air phpsphorus generates ozone slowly, as the 
phosphorus soon becomes coated, which prevents the action of the air. There 
is a connexion between the shining of phosphorus and its generation of ozone, 
so that this production exists in proportion to the intensity of the illumination; 
but we are ignorant of the cause of this connexion. 
If we well wash air ozonized by phosphorus and place in it a piece of car- 
bonate of ammonia, so that the gas reacts alkaline, and wash the gas again, it 
still gives all of the characteristic reactions of ozone. 
t According to Schoenbein's experiments, 1,000 grammes of phosphorus are 
capable of converting 1,720 of oxygen into ozone. By another trial he gives 
0.43 •gramme as the yield of ozone by 1 gramme of phosphorus. By hanging 
'silver leaf in a vitriol carboy filled with ozonized air, he could deozonize the 172 
OZONE AND ANTOZONE. 
same in four hours; and, by repeating the process for several weeks, he was 
able to prepare as much as 20 grammes of the peroxide of silver. Ozone 
results also from the slow oxidation of pure ether, effected by the means of a 
platinum spiral heated to redness and placed in the vapoi- of the ether. Accord- 
ing .to Schoenbein the combustion of hydrogen, carbide of hydrogen, and of 
kindred gases, produces ozone. 
The odor pf ozone is so powerful that airmontaining only one millionth of it 
has a decided smell of the gas. Ozonized air raised to the temperature of 
482° to 572° Fahrenheit, is deprived instantly of this body. 
A very characteristic action of ozone consists in its polarizing effects upon 
the metals, particularly upon platinum, gold, and, to a less extent, copper. An 
ozoniferous atmosphere behaves like one containing chlorine or brofliine. If a 
slip of gold or platinum is immersed in an ozone atmosphere, it acquires a nega- 
tive polarity in a few seconds. When such a slip is united with an ordinary 
one and the pair is plunged in acidulated water, a current is generated which 
act$ powerfully upon the needle of the galvanometer. Antozone, also, polarizes 
platinum negatively, but less so than ozone. 
In the preparation of ozone by phosphorus, an odor characterized as "garlic'' 
is first perceived. Gold or platinum, immersed in such air, is polarized posi- 
ticeUj, and this condition may remain for a considerable time if the tempera- 
ture be low. Presently, with a temperature of 53.6° to 60.8° Fahrenheit, the 
gas exchanges its " garlic" for an ozone smell; and, at the same time, the metal, 
after quickly passing Volta's point of indifference, acquires a negative polarity. 
The least moisture deposited upon the metal, also an elevated temperature, pre- 
vent, or, if present, destroy this polarization. It is also lost in the air gradu- 
ally, and immediately in hydrogen gas, which even communicates a positive 
polarity. 
Ozone is absorbed neither by water, caustic ammonia, nor baryta, sulphuric 
acid, or dry chloride of calcium. 
Schoenbein attributes many of the reactions of oxidation by the " nascent 
state" of the gas to the presence of ozone. 
Dr. Phipson has given many of such examples of polarization explanatory 
of the "status nas^ens" in a prize essay which is contained in the Smithsonian 
Report for 1862. 
A paper saturated with a solution of iodine is quickly bleached in an ozone 
atmosphere; the product, howeyer, does not react acid, and in contact with 
oxidizable bodies, such as sulphurous acid, sulphide of hydrogen, phosphorus, 
hydriodic acid, metals- like zinc and tin, or protoxides like those of. tin or lead, 
the paper becomes brown again from iodine. 
Solutions of chlorine and bromine act in the same manner; and it is this 
fact, together with the chemical analogies existing between ozone and the 
halides, which led Schoenbein to assign to ozone a similar nature. 
In the presence of strong bases, such as hydrates of lime or potassa, the 
nitrogen of the air may be oxidized to nitre by the action of ozone. Three 
thousand litres of ozonized air, agitated with milk of lime, furnish 5 grammes 
of saltpetre. Ozone liberates iodine from the iodide of potassium more fyeely 
in the sun than in the daylight; but when starch is present, the blue iodide of 
starch is bleached by the light. By renewed action of ozone it becomes ' blue 
again, and the bleaching and bluing may be repeated until the iodide of . pptas- 
sium is transformed completely into iodate of potassa; when ozone is no logger 
capable of producing the blue tinge. According to Baumert, the first effect 
of ozone upon this salt is the decomposition to caustic potassa and iodine, 
which react to form iodate of potassa and iodide of potassium. The ozone 
acts upon this iodide as before, until at length the halide is completely oxidized 
to iodate of potassa. 
The yellow prussiate of potassa is converted quickly into the red prussiate OZONE AND ANTOZONE. 
173 
by ozone. A crystal of the former salt placed in an ozone atmosphere be- 
comes gradually red, the color proceeding from the outside to the inside, and 
the solution of ferrocyanide of potassium experiences this change very readily 
when agitated with ozone. 
The metals arsenic, antimony, iron, zinc, tin, lead, bismuth, silver, and mer- 
cury, are oxidized instantly by ozone, and deprive thereby any atmosphere con- 
taining that gas. 
The metals are not oxidized with equal facility. Thus arsenic is oxidized 
much more readily than antimony, which affords an additional means of dis- 
tinguishing between these bodies in judicial inquiries. An arsenic spot in a 
strong ozone atmosphere is converted instantly to arsenic acid, while an anti- 
mony mirror requires several days for its disappearance. Dry mercury, or that 
covered with water, does not absorb ozone; if the metal be merely moistened, 
it takes up ozone readily, becoming yellowish upon the surface. 
Silver, in the state of leaf or sponge, absorbs ozone quickly, as has been 
stated already. This metal may be employed for separating ozone from ordi- 
nary oxygen. 
The more readily oxidized metals, as protoxides of manganese, iron, tin, &c., 
as well as those which, like protoxides of silver and lead, are not so easily 
changed to a higher state of oxidation, are peroxidized by ozone. 
A solution of the sulphate of the protoxide of manganese is browned in- 
stantly in ozone from the above cause, and, according to Schoenbein, this reac- 
tion is perceptible in a dilute solution of sulphate of zinc, which contains as 
an impurity only of manganese. If hydrated oyide of lead be spread 
upon paper, or if basic acetate of lead be employed, ozone will communicate 
to the paper first a yellow, then a red, and finally a brown coloration from the 
peroxidation. 
If the lead paper be blackened by means of sulphide of hydrogen, it may 
be bleached in ozone, which is due to the production of the white sulphate of 
lead. 
Organic bodies are very readily oxidixed in ozone, as shown by the experi- 
ments of Schoenbein, Baumert, Gorup von Besanez, &c. Thus wood, straw, 
cork, starch, humus, vegetable colors, caoutchouc-pure and vulcanized-the 
fats and fatty acids, alcohol, albumen, blood, &c., have been found to be all 
acted upon by this agent. Ozone bleaches litmus without first reddening it. 
Certain fungi become blue in the air, and the cut surface of an apple becomes 
brown by the action of ozone. 
Gum guiacum, which becomes gradually blue in the air, owes this change to 
ozone, as was first shown by Schoenbein, who employed this substance as a 
reagent for ozone. To prepare guiacum papers, one part of the gum is dis- 
solved in thirty parts of 90 per cent, alcohol. One gramme of ordinary alco- 
hol is charged with a few drops of this solution, and the paper slips are dipped 
therein and dried. The papers are blued rapidly in an ozone atmosphere. 
They lose this color when exposed to the air, but regain it in ozone, and the 
process may be repeated until the guiacum is fully oxidized. Certain metals 
and other bodies, especially nitrous acid, chlorine, bromine, peroxides of man- 
ganese, and lead, &c., will blue guiacum tincture. 
The following is Schoenbcin's method of determining ozone quantitatively 
in a mixture from its bleaching effect upon the solution of indigo : The ordi- 
nary solution is diluted with sufficient water to be just opaque blue. One hun- 
dred-grammes of this solution receive an equal weight of hydrochloric acid, 
and are then boiled. The heated liquid is treated with a solution containing 
Yq-q of chlorate of potassa until the blue color is exchanged for a brownish 
yellow. If, now, for the destruction of the 100 grammes of indigo solution, 
100 milligrammes of chlorate of potassa (which contain 39 milligrammes 174 
OZONE AND ANTOZONE. 
of oxygen) were employed, then 1 milligramme of oxygen would destroy 
J^_=2.564 grammes of indigo solution. Now, to this last quantity of the 
original indigo solution, containing hydrochloric acid, enough water must be 
added to dilute it to 10 grammes,* in order to obtain a normal solution of 
which 10 grammes will represent 1 milligramme of oxygen or ozone. One 
part of the above normal solution may be further diluted with 9 parts of water 
to yield normal test, in which 10 grammes will indicate yL milligrammes of 
ozone. 
The analysis is performed as follows, for example, upon a bottle of air 
ozonized by phosphorus : A little of the normal indigo solution is agitated 
with the air in the bottle for a few minutes, and the air is then tested for ozone 
by iodide of potassium starch, and the process is repeated until no ozone is 
indicated even by a slightly elevated temperature. Then, for every 10 
grammes of the normal indigo solution employed, 1 milligramme of ozone is 
present, and for every 10 grammes of the yL normal solution, of a milli- 
gramme of ozone has been found. 
Schoenbein discovered the remarkable bleaching properties upon indigo and 
other plant colors of certain bodies which appear to absorb ozone, without 
combining with it, and thus are in a position to yield the ozone again to other 
substances. These bodies have been called " ozone carriers." They are oil 
of turpentine, linseed oil, oil of lemons, tartaric and citric acids, ether, plati- 
num sponge and black, powder of silver, gold, and platinum, also metallic mer- 
cury. These substances, shaken witlrsolutions of indigo, litmus, cochenille, &c., 
discharge the color; with tincture of guiacum they yield a blue tinge, and give 
the same color with iodide of potassium starch. One of the most remarkable 
of the ozone carriers is the blood corpuscule. Ozonized oil of turpentine, 
shaken with indigo solution, bleaches it after a while, but if blood corpuscules 
are added, the decoloration is instantaneous. Platinum black is also very active 
in its bleaching effects. 
One of the best known ozone carriers is the oil of turpentine. If a bottle 
be filled with this body, exposed to the sun, and frequently shaken with air, 
removing the stopper from time to time to renew the air, the oil is speedily laden 
with ozone. After a time the oxidizing or bleaching effect of this oil is lost, 
probably from its ozone entering into combination with it. Its bleaching 
effect may be ascertained quantitatively by means of a solution of indigo. 
Schoenbein prepared an oil of which 1 gramme possessed the same bleaching 
power as 2 grammes of the best bleaching powder, (hypochlorite of lime.) 
The ozonized oil bleaches most rapidly when warm, but its absolute decolor- 
izing power is then less. All turpentine kept with access of air becomes 
ozonized, as may be seen from the bleached and corroded corks employed in 
closing the vessels containing it. Upon the animal organism ozonized oil of 
turpentine acts more energetically than oil not ozonized. According to Seitz, 
5 drops of ozonized oil throws into convulsions and kills a frog and destroys 
other small animals, while 20 drops of the pure oil produce no such effect. 
Not long since a statement prevailed that the disease called painter's colic is 
due, not to the lead absorbed, but to the oil of turpentine. If this be so, the 
ozonization of the turpentine may be the active agent for mischief, although 
the lead may also be hurtful. 
The existence of ozone in the atmosphere has been known since the discovery, 
of the body ; but the conditions which govern its presence, as well as the actual 
quantity of the gas, are yet undetermined. This arises from the small amount of 
ozone in the air, from the readiness with which this active oxidant is destroyed 
by the presence of bodies upon which it may act, and also for the want of a re- 
* Hence, in this case, 10-2.564=7.436 water will be needed. OZONE AND ANTOZONE. 
175 
liable quantitative test. The largest proportion with which the air has been 
artificially loaded with this substance amounts to -^oo of its volume. 
Ozone may be determined quantitatively by ascertaining the amount of 
iodine liberated from iodide of potassium; by determining the quantity of pe- 
roxide of silver which it produces ; or by finding the proportion of indigo solu- 
tion which it decolorizes. But this kind of test has never been applied to a 
great extent in determining the atmospheric ozone in long series of observa- 
tions, owing to the difficulty and labor of applying it. 
A large volume of air brought slowly to act upon a small proportion of the 
reagent is necessary for this purpose. In aspirating twenty-four litres of external 
air during a period of two and a half hours, concentrating its action upon a 
circle of an inch in diameter on a delicate iodide of potassium starch paper, 
I was unable to detect the slightest ozone reaction, although a slip of similar 
paper exposed all day to the free atmosphere was colored sensibly. 
The ordinary mode of observing ozone in the atmosphere consists in ascer- 
taining the amount of color produced upon paper containing iodide of potas- 
sium and starch, using precautions against the bleaching effect of the light 
upon the iodide of starch developed by the ozone. A scale of shades of color 
is employed for determining, by comparison, the proportion of the gas in ques- 
tion present in the atmosphere. Boehm found that this test, prepared from 
the same recipe by different persons, gave varied results. According to Osann's 
formula, thirty-two grains of starch are rubbed in a mortar, with the same 
quantity of cold water ; three grains of iodide of potassium are then dissolved in 
four ounces of boiling water, and the solution is added to the starch and well 
incorporated with it. After boiling once more, the test is cooled and placed in 
a bottle for use. When reagent paper is required, slips of Swedish filtering 
paper are shaken up with the starch liquid, and then dried. This paper is in- 
stantly colored of a deep shade of blue when exposed to the ozonized air of a 
bottle containing phosphorus and a little water. Exposed during the night to 
the atmosphere, the coloration by ozone is very decided. 
In the ordinary atmospheric ozone observations the velocity of the air-cur- 
rent which traverses the reagent paper influences the result by bringing a greater 
proportion of ozone upon the test in a given time. The determinations which 
have been hitherto made are very vague, unsatisfactory, and yield but rude 
comparative results as to the subject in question. 
Notwithstanding this difficulty, theories have not been wanting as to t-he in- 
fluence of ozone upon the health. The oxidizing action of ozone upon organic 
substances as shown by Gorup von Besanez, the phenomena of ozone carriers, 
such as oil of turpentine, platinum sponge, and the blood corpuscules, have 
facilitated the formation of such theories. 
Dr. Smallwood, in a long series of observations upon the atmosphere of Can- 
ada during the prevalence of the cholera and at other times, favored the in- 
ference of a deficiency of ozone during the epidemic. 
Dr. Moffatt concluded, from a large number of observations in England, that 
the ozone in the atmosphere plays an important part in controlling or prevent- 
ing epidemics, which it effects by removing the infectious matter from the air. 
During the prevalence of the cholera at Newcastle, in 1853, this gas was at 
its minimum. From August 24 to September 11, 1854, when the disease was 
at its height in London, ozone was observed only once, and then in but small 
quantity. On the 10th September a south wind prevailed, by which the ozone 
was found to increase, and the cholera cases diminished. During the Crimean 
war the surgeons of the French army established the following facts : 
1. In proportion as the ozonoscopic papers were more colored in the air, the 
more numerous were the sick taken to each of the hospitals. 
2. When the temperature was higher, there were fewer sick and fewer deaths. 176 
OZONE AND ANTOZONE. 
3. At the three observatories the curves designating the proportion of ozone 
were essentially the same. 
4. The curves for temperature were also identical. 
5. At observatory No. 1 the quantity of ozone was inversely proportional 
to the number of deaths, while in observatory No. 2 this proportion was a 
direct one. 
Bineau detected ozone but seldom in the air of Lyons, although he observed 
it always in the air of the neighboring country. He attributes the deficiency in 
the city to the action of organic matter in the air. 
Pless and Pierre discovered 0.02 millegramme of ozone in 255 lifres of at- 
mospheric air. 
Zenger found in twelve experiments from 0.002 to 0.01 milligramme of this 
body in 100 litres of air. 
R. Angus Smith ascertained that the air of Manchester did not react with 
ozonoscopic paper, nor was there any reaction in the country when the air had 
first traversed the city; which he attributes to the absorption of ozone by the 
products of combustion, (antozone ?) arising from the large amount of coal burned 
in the city. 
C. Kosmann ascertained that in Strasburg, and at a short distance from the 
city, there was more ozone in the air of the country than in that of the city. 
In the city, the ozone maximum occurred in the daytime; in the country, at 
night. He found also, by the action upon Schoenbein's test paper, that the 
green portions of all plants exhale ozone. 
Mr. Carey Lea discovered that the growth of plants is retarded in an atmo- 
sphere strongly impregnated with ozone. 
A. Poey found that in the city of Havana the ozone reaction diminished 
with the elevation, while in the country the reverse was observed. He also 
discovered that the moisture of the atmosphere influenced the amount of ozone. 
I ascertained that the air of the public grounds in Washington yielded, at 
night, abundant evidence of ozone, while the atmosphere of the streets of the 
city, observed at the same time, indicated an absence of this gas. 
Dr. W. B. Rogers found that the air passing over Boston was deprived of 
its ozone by the emanations from the city. 
M. Hozeau, of Rouen, inferred, from a series of observations which extended 
over four years, that the atmospheric ozone is least in February, begins to in- 
crease in March, and reaches its maximum in May and June, after which month 
it diminishes to its minimum in February. 
J. Boehm has given the results of four years of regular observations of ozone, 
made in the city and environs of Prague. His ozonoscopic paper was observed 
and changed at 7 a. m. and 7 p. m., the proportion of ozone being determined 
by the depth of shade of the color produced. He found that the ozone bears 
no relation to the relative humidity, rain or thunder storms, clouds, &c., but is 
intimately connected with the force and direction of the wind, which was gen- 
erally from the west when the phenomenon of color was observed. The reason 
of this fact is the relative position of the observatory to the city of Prague, so 
that all easterly winds passed over a thickly-settled portion of the town, by the 
emanations of which they were deprived of their ozone. 
In the country and suburbs, Boehm found ozone constantly present. With- 
out expressing a decided opinion upon the relation of ozone to health, this 
physicist calls attention to the fact that in Koenigstadt, a place not particu- 
larly noted for its salubrity, he obtained as decided reactions of ozone as upon 
the healthiest mountain, and that the coloration of the test paper is more de- 
cided in Vienna, a city noted for its lung and typhoid fevers, than in Prague, 
which is ranked justly with the healthiest towns. 
From what is known at present respecting "antozone," it would seem that 
this body plays an important part in depriving the atmosphere of ozone. 177 
OZONE AND ANTOZONE. 
In judging from the reaction upon iodide of potassium starch paper, ozone is 
always in the free atmosphere in variable, but small, quantity. Such test pa- 
pers are not blued when closed in a bottle, and scarcely so, if at all, in a room. 
By exposure to the external atmosphere the effect upon them is extremely va- 
riable. Sometimes in cities it is imperceptible. According to Osann, the color- 
ation is greater by night than by day, and is more decided towards sunrise, at 
the time when the atmospheric moisture is precipitated. It is greater in winter 
than in summer, stronger with clouded than with clear sky, and is especially 
powerfulwith snow clouds. Every flake of snow falling upon the test paper 
produces a blue stain. By atmospheric electrical discharges ozone is, as might 
be expected, very prevalent. Schoenbein calls attention to the fact that the 
odor in the neighborhood of places struck by lightning is exactly that of ozone. 
The whole subject of ozone, whether in its physical or physiological rela- 
tions, is intensely interesting, and promises, when understood, to be the means 
of solving many problems in the sciences now so difficult to be comprehended. 
No field of research appears to promise so rich a harvest to the skilled and 
patient observer.