Rodolfo Amedeo Lanciani.

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the Jolly's mercury pump. Between the drying tube and the
electrizing tube is a oarometer tube by which the exhaustion
may be regulated. After thoroughly washing out the entire
apparatus with pure oxygen, it is thoroughly exhausted, the
cock beyond the electrizing tube closed, and tne one connected
with the receiver gradually opened, the electrizing tube thus
filled with oxygen, and this submitted to the action of the
sUent electric discharge* The electrized oxygen now passes
successively through the solution of potassium iodid and the
water, upon the surfiwe of which latter liquid the dense anto-

* The electrimg tube of Ton Babo is described in Prot Johnson's abstract
above alluded ta



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Metsmer^s Besearches upon Mectirized Oxygen. 215

zone-mist appears, increasing -momentarily in density until the
flask, two inches in diameter, becomes perfectly opake. This
experiment, performed in precisely this way, was repeated
twelve times, and always with the same result ; Dr. Meissner
believes therefore, that neither hydrogen nor nitrogen is in any
way concerned in the production of this peculiar mist

The second point, that the presence of aqueous vapor in the
electrizing tube is not necessary to the result, was established
by filling this tube with pure oxygen dried over anhydrous
phosphoric acid, then electrizing it, and, after intermitting the
current, passing it through the solutions. The result- was the
same as before.

Nitrogen having been shown to be without effect on the pro-
duction of the mist, the especial apparatus for the electrolytic
preparation of oxycen was given up, and this gas was obtained
from potassium cmorate, and washed with a solution of potas-
sium lodid. In the next experiment this oxygen passed from
the gasometer through a wash-bottle filled with potassium
hydrate solution, then through a U tube filled with calcium
cnlorid, then through another wash-bottle containing sulphuric
acid, and finally over anhydrous phosphoric acid, to the electriz-
ing tube, being now free from chlorine, carbonic acid, ammonia,
and moisture, though containing perhaps a trace of nitrogen*
On passing a stream of this electrized oxygen, first over phos-
phoric anhydrid, then into iodid of potassium solution, and
afterward through water, the dense cloud appeared as before.
Meissner believes therefore " that these experiments, not once
only or a few times repeated, but performed very firequently,
prove the following pomt : that the mist formed by de-ozonized
electrized oxygen with acjueous vapor, appears when neither
chlorine, nitrogen, ammonia, hydrogen, car Donic acid nor watery
vapor is present in the tube where the electrizing occurs ; and
that the presence or aid of neither of these substances is neces-
sary afterward for its formation. That in other words, the mist-
phenomenon requires only dry electrized oxygen, the potassium
lodid used for de-ozonization, and the vapor of water, for its
production."

The third point, that the potassium iodid acts simply by ab-
sorbing the ozone, and thus setting the mist-forming oxygen
free, Meissner proves by replacing this substance by a great va-
riety of other bodies, dmering wiaely in chemical properties and
agreeing only in the property of absorbing ozone. Sodium pyro-
gallate, — ^wmoh must be free from even a trace of gallic acid —
potassium ferrocyanid, potassium manganate, the higher sul-
phids of potassium and sodium, barium sulphid — ^the hydrosul-
phuric gas being removed by passing the de-ozonized oxygen
through a solution of cupric sulphate before entering the re-



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216 Mdsmer^s Besearches upon Mecdrized Oxygen,

ceiver of water — ^ammonium sulphid, hydrosulphxtric add, sul-
phurous acid — either free or as sodium sulphite — and ammonio-
lerrous tartrate, were all used with good results, the ozone being
entirely removed. It is not necessary however, to absolutely
de-ozonize the oxygen, in order to produce the mist ; partial
absorption will produce it, though it is weaker in proportion to
the amount of ozone remaining. By using potassio- or sodio-
ferrous tartrate, instead of the ammonia salt, such a partial ab-
sorption is eflfected. The same is true of certain metals, when
moistened with water; lead, zinc, copper, iron, tin, cadmium,
antimony, aluminum, and thallium au giving the mist, though
lead, zinc and aluminum are the best for this purposa Meissner
compares the mist rising from these metallic bars to the doud
which rises from moistened phosphorua Even carbon, in the
form of gaa-carbon, and sometimes animal charcoal, effects this
absorption. The noble metals gold and platinum remain com-
pletely unaltOTed in both moist and ary ozonized oxygen.
Chemically pure silver in the dry gas remains unchanged except
at single points which show a beautiful greenish play of colors,
without a trace of black peroxyd, into which, in the presence
of moisture, it is so rapidly converted. Mercury, perfectly dry
and still, remains unaltered, though on the least agitation a* film
appears on its surface, by which it adheres strongly to the glass.
On replacing the ozonized by common oxygen, the mercury
becomes again mobile, a black powder — of mercurous oxyd
probably— ^ing left. If the mercury be moist, reddish mer-
curic oxyd resTUta With none of these latter metals, however,
is any mist formed.

Though these experiments prove conclusively that no single
substance can be yielded by such widely different de-ozonizing
substances, to form the mist, yet may not each yield one, which,
though unlike the others in all else, may have, in common with
them, this mist-forming property? This hypothesis, Meissner
considers disproved by the fact that the mist is chemically
identical, whatever the absorbing agent It may be agitated
with, or passed through water, not only without losing, but
often with actual increase o^ its properties. It may be passed
through dilute sulphuric acid or {Qkaline solutions unchanged.
" In a word, the mist which appeara in my experiments under
the given conditions, is neither acid nor alkaline, consists of a
body neither soluble nor insoluble in water, but is solely a
mechanical or adhesive combination of oxygen and water,
which, when washed and collected' in a gas-nolder, gradually
disappears, fine fluid drops collecting upon llie walls of the
vessel which when examined are found to be pure water, con-
taining possibly under certain conditions, a trace of hydrogen
peroxyd." Wnen passed through strong sulphuric acid, or over



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Meissner^s Besearches upon Electrized Oxygen, 217

calcium chlorid or phosphoric anhydrid, the cloud disappears
because of the removal of the water ; but it reappears again,
though weaker, when brought a^ain in contact with water.
The unwashed mist, indeed, contams impurities coming from
the absorbent employed ; as iodine and traces of iodic acid
from the potassium lodid, anunonia, hydrosulphuric gas, and
probably, also, traces of ammonium nitrate. But all de-ozoniz-
ing substances do not yield such impurities, and even these may
be removed without affecting the mist

Again^ may not the mist be produced either by the action of
the oxygen unaffected by the electricity, or by the action of
the ozone which thus results ? Oxygenitself, under no known
conditions, exhibits this property ; and as to ozone, the above
experiments show that it may be completely removed by vari-
ous absorbing solutions without interfering with the pheno-
menon. Indeed, the mist is the stronger, the more perfect the
removal of the ozone from the electrized oxygen. So that,
contrary to the opinion expressed in the first paper, not a trace of
mist appears until the ozone has been, at least partially, removed.
That this mist is not due to a compound of ozone with water,
is established by the fact that contact of the electrized oxygen
with water before de-ozonization is prejudicial to its subsequent
production. Further, such a compound must hold the ozone
with such force as to prevent such easUv oxydized bodies as
potassium iodid, pyrogallic acid, or alkaline sulphids, from
withdrawing it, ana yet be at the same time one of the most un-
stable of substances. And moreover, were there such a com-
pound of ozone and water, the de-ozonized oxygen, after care-
rdl drying, would yield water when subjected to a high tempera-
ture ; Meissner however, has failed entirelv to detect any mois-
ture under these circumstances. Finally, the only known
compound of water and oxjgen, hydrogen peroxyd, forms no
such mist If therefore, neither the ozone itself, nor any com-
pound of it, is concerned in the phenomenon, there must be
contained in the pure dry electrized oxygen, besides the un-
altered oxygen ana the ozone, some third body, a third condi-
tion or modification of oxygen, to which the result is to be
ascribed.

Assuming now the existence of antozone, Meissner proceeds
to study more minutely the action of absorbing agents, with
special reference to this substance. He divides them into two
classes, one of which removes ozone alone from the solution, the
other absorbs both modifications. The first substance examined
is pyrogallic acid itself, by which the ozone is completely
removed, the solution becoming beautiful hyacinth-red in
color; but, unlike the action of the alkaline pyrogallates, the
fi^e acid removes also the antozone, so that not a trace of mist

Ax. JouB. Soi.— SsooKD 81BIB8, Vol. L, No. 14a>8EPT., 187a
14



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218 Meissner^a Researches upon Electrized Oxygen.

appears when the gas is subsequently passed through water.
On adding a few drops of sodium hycfrate, the liquid becomes
dark brown, and the mist at once appears. Meissner accounts
for this result, by supposing that in the oxydation of the free
acid both ozone and antozone are taken into combination in
equal proportions, while in that of its alkaline salts, the ozone
combines to a larger extent than the antozona Another sub-
stance exammed is sodium thio sulphite (hypo-sulphite). When
the electrized oxygen passes through a concentrated solution of
this salt, both ozone aild antozone disappear, not a trace of mist
being formed. This result is especially noticeable, inasmuch
as sodium suli)hite removes only the ozone, and inasmuch as
the product is, in both cases, sulphuric acid. Since to oxydize
sulpnurous acid, two equivalents of oxygen are requirea for
every two of sulphur; and to oxydize thio-sulphurous acid
four equivalents of oxygen are needed to two of sulphur;
Meissner believes that the two of oxygen in the former case are
ozone ; while the two times two in the latter are not of equal
value, one pair being ozone, the other antozone, atoms. So
also by the use of arsenous acid as an absorbent, both modifi-
cations are removed from the electrized stream of oxygen, both
when the acid is free as well as when its sodium salt is em-
ployed. By using a very dilute solution, or the ordinary satu-
rated solution in small amount, the ozone may be imperfectly
removed ; and by passing the gas afterward through potassium
iodid solution to remove the ozone entirely, the antozone which
remains gives a feeble mist with water ; thus showing here also,
that ozone and antozone are absorbed by the arsenous add in
equivalent proportions. Here again Meissner believes that of
the two atoms needed to make arsenic acid fix)m arsenous, one
is ozone, the other antozona Mercurous nitrate, in concentrated
solution, absorbs, under the conditions of the experiment, both
ozone and antozone only partially, though equally ; thus acting
like arsenous acid. The partial absorption in these cases is to
be distinguished from that eflfected by the metals or alkaline
ferrous salts ; in the former case both the oxygen modifications
are equally absorbed, while in the latter the ozone is almost
entirely removed, but the antozone is unaflfected.

Of particular interest is the action of electrized oxygen upon
potassium hydrata "When firagments of this substance slightly
moist upon their surfiaces are placed in a horizontal glass tube,
and subjected to the current of electrized oxygen, they shortly
become covered for a short distance from the end of the tube,
with orange-yellow potassium peroxyd. But however long the
experiment continues, the other pieces remain unchanged, and
not a trace of either ozone or antozone issues from the tuba
So soon as the electrical action ceases, and ordinary oxygen



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Meis&ner^s Researches upon Electrized Oxygen. 219

again enters the tube, the yellow crust disappears, to be a^ain
formed as often as the electrized oxygen passes over it Since
the peroxyd is at once decomposed by water, and since too, the
maximum production is very soon reached, it would seem that
the peroxyd is successively produced and decomposed in the
experiment, causing in this way the disappearance of ozone
and antozone and yielding common oxygen. Absolutely ' dry
hydrate has no effect on the electrized oxygen. In aqueous solu-
tion, the formation of the yellow peroxyd takes place only in
the narrow tube which dehvers the gas ; but as the antozone
and the ozone are materially lessened, though never absolutely
destroyed in any of Meissner's experiments — ^it is fair to infer
an action similar to that in the tube. Sodium hydrate acts
similarly though less energeticallv ; the two modifications
appear moreover to be unequally absorbed, more of the
antozone disappearing than of the ozone. These r^ults
illustrate well the two classes of absorbing agents ; in the
one case complete absorption of the antozone takes place
with that of the ozone, in the other a portion of the antozone
remains. In the one case partial absorption of both is equal,
in the other unequal One of these classes requires for its
oxydation more ozone than antozone, the other requires them
in equal proportions ; possibly there is a -third class requiring
more antozone than ozona

An important practical application is made of these facts to
the employment of potassium iodid as an absorbinc solution.
A neutral solution of this substance becomes alkaline when
subjected to the action of ozone, and contains free potassium
hycfrate, which, acting as above, diminishes the antozona By
so arranging the apparatus that acid or alkali can be added at
pleasure to the iodid solution, the mist is seen to be diminished
on making it alkaline and increased when it is made acid.
The neutral solution of potassium iodid is not therefore a suita-
ble de-ozonizing agent, if it is desirable subsequently to pro-
duce the mist It should be previously acidulated with hy-
drochloric or sulphuric acid, especially where the quantity of
antozone is small Though for very delicate investigations
Meissner prefers an aqueous solution of iodina

The same injurious action of free alkali appears with ferrous;
oxyd and pyrogallic acid solution. It is completely obviated
by using anmionia in place of potassa or soda, ammonium
pyrogallate and ammonio-ferrous tartrate being fer preferable
to the same compounds of the fixed alkalies. Even with the
sulphids this is true ; the strongest antozone-mist Meissner ob-
served was obtained by using ammonium sulphid as de-ozonizer,
this compound absorbing more ozone and less antozone than anj-
other substance tried. W hen ammonium hydrate is submitte'' .



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230 Meissner^s Besearchea upon Electrized Oxygen.

to a stream of electrized oxygen, the ozone is partially absorbed
by it, and the antozone cloud rests on its sunace. fey passing
the mist through dilute sulphuric acid, its ammonia may be re-
moved ; and then, on collecting it in an open vessel, the water
which it deposits is found to contain nitric acid which comes
from Ae oxydation of the nitrogen of the air. Solutions of am-
motdum carbonate act in the same way. The energy with
which ammonium sulphids absorb ozone, is fturther shown by
the &ct that, like moist phosphorus, some of them can polarize
common oxjgen, absorbmg tne ozone and emitting a powerful
antozone-mist Under the name "Liquor fumans Boylii,"
such an ammonium sulphid has long been known. It fames
strongly, but only with oxygen ; neither hydrogen nor nitrc^en
causing it Every unsaturated ammonium sulphid solution, if
it contain suf&cient sulphur, is such a faming liquor. By pass-
ing pure oxygen through it and then through water, a aense
mist is obtamed which can be washed, be dned, and then be
reproduced ; a true antozone mist

A singular cause of error in his previous paper is hero
pointed out "When dry air is electrized, the mist is easily
obtained on contact with water, even without the previous use
of any de-ozonizing solution. Meissner hence stated that the
mist could be formed without previous removal of the ozone.
But in fact the nitrogen of the air, being oxydized to nitric
acid by the ozone, acts as a de-ozonizing agent He obtained
however the same result with pure oxygen. But upon examin-
ing his apparatus, he found a cork previously used with a
solution of potassium iodid, which had iodine upon it and thus
acted as the de-ozonizer. In his later researches all these
sources of error were avoided, and the conclusion established
that to produce the antozone mist, the ozone must first be wholly
or partially removed. *

"As the result of many oft-repeated experiments," says
Meissner, "it may be asserted that there is no single fluid
through which, or no single solid over which, electrized oxygen
can be passed without exerting some action upon it; even
when the substance is itself not oxydable, or does not fix in
chemical combination any constituent of the electrized oxygen,
some action takes place by which the amount of ozone or
antozone in the stream of oxygen is more or less diminished."
Not only finely divided gold and platinum, but also entirely
indifferent bodies, such as asbestus, cotton, calcium chlorio,
charcoal-powder, or finely broken coal, destroy tiie ozone and
antozone in electrized oxygen. Even after the removal of tiie
ozone, if the mist be passed over finely granular calcium
chlorid, the antozone will disappear. Tlie same is true of
jiquids ; a sulphuric acid valve included in an apparatus to



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Meissner^a Researches upon Electrized Oxygen, 221

f)revent the entrance of moisture into the electrizing tube,
eeaens the amount of ozone and antozone obtained.

n.

Section 11 treats of the '^ Quantitative estimation of Ozone,
and the contraction of volume on electrizing oxvgen." The
ai)paratus employed is similar to that above describ^ the elec-
trizing tube being widened to enclose a thermometer, and hav-
ing a delicate mercury-manometer attached to it A bulb-ap-
paratus of simple construction holds the de-ozonizing solution,
and a second simOar one contains sulphuric acid. The last bulb
of the former apparatus contains fine asbestus, which is found
to destroy almost perfectly the cloud-forming substance, and so
to retain the iodic acid and iodine carried over with it Both
bulb-tubes have wires by which they may be attached to the
balance. In making an observation, the apparatus is filled
with pure oxygen, the manometer, barometer, and thermometer
carefully noted, the oxygen electrized, time allowed for the
temperature to be equau^d, communication established with
the manometer, the mminution of volume ascertained, and the
quantity of active oxygen determined : 1st, by the increase in
weight of the bulb apparatus, and 2d, by titration with sodium
thio-sulphite or occasionally, sodium sulphite. The fi-ee iodine
is first determined, and then the solution is acidulated with
hydrochloric acid; the hydriodic acid thus set free reacts
with the iodic acid to set free more iodine, which is then
titrated by itself Hence every iodine-equivalent represents
one of oxygen, and by dividing the weight of iodine found
by 15-875 (127-^8) the quantity of oxygen absorbed is ascer-
tained; or in other words, the oxygen absorbed shown by
the increase of weight, must be to the iodine set free as mea-
sured by titration, as 1 : 15*875. In the experimental results
given in the table, this proportion is not reached, but varies
&om 1 : 14*9 to 1 : 18. Tnis variation, observed by other
experimenters, was investigated. It was found not to be due
to the action of the unozonized oxygen, nor to any loss oi
iodine in the gas-current, nor to imperfections in the titrition
itself; nor did it appear when the iodine was completely
oxydized to iodic acid, both weighing and titrating then giving
the same results. These last experiments, Meissner believes in
passing, establish the fact that ozone is simply a modification
of oxygen, not an oxydized water; that no hydrogen peroxyd
is produced in it ; and that the method of experimenting here
employed is free from errors. He believes too, that the varia-
tions observed when the potassium iodid is incompletely oxyd-
ized, may be due to the production of some intermediate oxyd
of iodine ; and hence, regards the method by weight as less
liable to error in estimating the amount of ozone, than the



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222 Meismer s Researches upon Electrized Oxygen.

method of titration. I^ however, the solution of potassium
iodid be either veiy dilute or very concentrated, or particularly,
if it be acidulated ; or, what is the same thin^, if a solution of
hydriodic acid be used, — ^in which case no iodic acid is formed
— ^then the method of titration becomes accurate, the results
agreeing with those obtained by weight The objections how-
ever to the acidulated potassium iodid solution are : 1st, there
is a loss of iodine, carried off by the antozone ; and 2d, the
iodine separates in thick masses of crystals which stop entirely
the delivery tube. When too, the ozone enters the absorbing
solution very dense, as when a given portion of oxygen is
electrized for a long time, and then passed at once into it, the
differences between the results of weighing and titrating are
very much increased ; the results then varying from 1 : 8 to
1 : 4, instead of 1 : 15-8.

The experiments on the influence of electrical tension upon
the production of ozone showed that with a velocity of 2*25 to
2*50 liters per hour, a spark of 1'5 centimeters gave "006 grms.
ozone, of 4 to 5 centimeters "0274 grms, of 5 to 6, 0322 grms.,
and of 6 to 7 centimeters 0889 grams, as the maximum ; no
increase being obtained with that apparatus, on increasing the
length of the spark.

On the question of the contraction of volume on electrizing
oxygen, a series of twelve experiments, made with the appa-
ratus already described, show that, as a mean, the weight of
oxygen absorbed as ozone, bears to a weight of oxygen equal
to the observed contraction, the ratio of 1*984 to 1 ; i e., essen-
tially of 2 : 1. That is to say, the portion of electrized oxygen
absorbed by potassium iodid, weighs twice as much as the
volume of oxygen which disappears during the electrization.
This result was so extraordinary, that the experiment was care-
fully repeated, the potassium iodid being completely oxydized ;
the oxygen absorbed weighed 0O182 grams, the contraction of
volume 000938 grams, being virtually 2 : 1. Meissner is not
prepared to claim this numerical relation, however ; he simply
mamtains that the electrized oxygen absorbed by the ioaid,
weighs more than the volume corresponding to the contraction
observed. He then goes on to discuss the methods by which
Andrews and Tait, and von Babo and Glaus, came to different
results ; criticising in the former case, the apparatus used, the
formula for calculation, and the method of determining the
ozone by titration ; and in the latter, the use of a neutral solution
of potassium iodid having a wronff concentration, and the velo-
city of the stream of oxygen, botn of which, as shown above,
aflect the result As to Soret's results, which were made with
electrolytic oxygen, Meissner merely remarks that if made
with the use oi a neutral solution of iodid as absorbing agent,
as seems to be the case, they may not be reliable ; though not



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A. R VerrUl on a new species of Entozoa. 223

having prepared ozone in this way, he can pass no further
judgment upon them. No conclusion however, upon the den-
sity of ozone can be drawn by Meissner from his own experi-
ments, since the results obtained are due to both the modifica-
tions of oxygen produced by the electrization ; while the ratio
of the two present, is unknown.

Finally, Meissner takes up the question of the electrizing of



Online LibraryRodolfo Amedeo LancianiThe American journal of science and arts → online text (page 78 of 109)