PROF. H.E. ROSCOE, President, in the Chair.
Mr. Vivian Lewes read a paper on "_Pentathionic Acid_." In March last the
author, at the suggestion of Dr. Debus, undertook an investigation of
pentathionic acid, the existence of which has been denied. The analyses
of the liquid obtained by Wackenroder and others, by passing sulphureted
hydrogen and sulphur dioxide through water, are based on the assumption
that only one acid is present in the solution, and consequently do not
establish the existence of pentathionic acid; as, for example, a mixture of
one molecule of H_2S_4O_6 and one molecule of H_2S_6O_6 would give the same
analytical results as H_2S_5O_6. Moreover, no salt of pentathionic acid has
been prepared in a pure state. The author has succeeded in preparing barium
pentathionate thus: A Wackenroder solution was about half neutralized with
barium hydrate, filtered, and the clear solution evaporated _in vacuo_ over
sulphuric acid. After eighteen days crystals, which proved to be barium
pentathionate + 3 molecules of water, formed. These crystals were
separated, and the liquid further evaporated, when a second crop was
obtained intermediate in composition between the tetra and pentathionate.
These were separated, and the mother-liquor on standing deposited some
oblong rectangular crystals. These on analysis proved to consist of baric
pentathionate with three molecules of water. This salt dissolves readily in
cold water; the solution is decomposed by strong potassic hydrate, baric
sulphite, hyposulphites, and sulphur being formed. By a similar method of
procedure the author obtained potassium pentathionate, anhydrous, and with
one or two molecules of water. The author promises some further results
with some other salts of the higher thionates.
The president said that the society had to thank the author for a very
complete research on the subject of pentathionic acid. He, however, begged
to differ from him as to his statements concerning the researches of
Messrs. Takamatsu and Smith; in his opinion these authors had proved the
existence of pentathionic acid. He hoped that the crystals (which were very
fine) would be measured.
Dr. Debus said that no one had previously been able to make the salts of
pentathionic acid, and expressed his sense of the great merit due to the
author for his perseverance and success. The paper opened up some highly
interesting theoretical speculations as to the existence of hexathionic
acid. If potassium tetrathionate was dissolved in water it could be
re-crystallized, but potassium pentathionate under similar circumstances
splits into sulphur and tetrathionate; but a mixture of tetrathionate and
pentathionate can be re-crystallized. It seemed as if the sulphur when
eliminated from the pentathionate combined with the tetrathionate.
Dr. Dupré asked Dr. Debus how it was that a molecule of pentathionate could
be re-crystallized, whereas two molecules of pentathionate, which should,
when half decomposed, furnish a molecule of tetra and a molecule of
pentathionate, could not.
Dr. Armstrong then read a _"Preliminary Note on some Hydrocarbons from
Rosin Spirit."_ After giving an account of our knowledge of rosin spirit,
the author described the result of the examination of the mixture of
hydrocarbons remaining after heating it with sulphuric acid and diluting
with half its volume of water and steam distilling. Thus treated rosin
spirit furnishes about one-fourth of its volume of a colorless mobile
liquid, which after long-continued fractional distillation is resolved into
a variety of fractions boiling at temperatures from 95° to over 180°. Each
of the fractions was treated with concentrated sulphuric acid, and the
undissolved portions were then re-fractionated. The hydrocarbons dissolved
by the acid were recovered by heating under pressure with hydrochloric
acid. Besides a cymene and a toluene, which have already been shown to
exist in rosin spirit, metaxylene was found to be present. The hydrocarbons
insoluble in sulphuric acid are, apparently, all members of the C_nH_{2n}
series; they are not, however, true homologues of ethylene, but hexhydrides
of hydrocarbons of the benzene series. Hexhydro-toluene and probably
hex-hydrometaxylene are present besides the hydrocarbon, C_10H_20, but it
is doubtful if an intermediate term is also present. It is by no means
improbable, however, that these hydrocarbons are, at least in part,
products of the action of the sulphuric acid. Cahours and Kraemer's and
Godzki's observations on the higher fractions of crude wood spirit, in
fact, furnish a precedent for this view. Referring to the results obtained
by Anderson, Tilden, and Renard, the author suggests that rosin spirit
perhaps contains hydrides intermediate in composition between those of
the C_nH_{2n-6} and C_nH_{2n} series, also derived like the latter from
hydrocarbons of the benzene series. Finally, Dr Armstrong mentioned that
the volatile portion of the distillate from the non-volatile product of the
oxidation of oil of turpentine in moist air furnishes ordinary cymene when
treated in the manner above described. The fact that rosin spirit yields a
different cymene is, he considers, an argument against the view which
has more than once been put forward, that rosin is directly derived from
terpene. Probably resin and turpentine, though genetically related, are
products of distinct processes.
The next paper was _"On the Determination of the Relative Weight of Single
Molecules,"_ by E. Vogel, of San Francisco. This paper, which was taken as
read, consists of a lengthy theoretical disquisition, in which the author
maintains the following propositions: That the combining weights of all
elements are one third of their present values; the assumption that equal
volumes of gases contain equal numbers of molecules does not hold good;
that the present theory of valency is not supported by chemical facts, and
that its elimination would be no small gain for chemistry in freeing it
of an element full of mystery, uncertainty, and complication; that the
distinction between atoms and molecules will no longer be necessary;
that the facts of specific heat do not lend any support to the theory of
valency. The paper concludes as follows: "The cause of chemical action is
undoubtedly atmospheric pressure, which under ordinary conditions is equal
to the weight of 76 cubic centimeters of mercury, one of which equals 6.145
mercury molecules, so that the whole pressure equals 467 mercury molecules.
This force--which with regard to its chemical effect on molecules can be
multiplied by means of heat--is amply sufficient to bring about the highest
degree of molecular specific gravity by the reduction of the molecular
volumes. To it all molecules are exposed and subjected unalterably, and
if not accepted as the cause of chemical action, its influence has to be
eliminated to allow the introduction and display of other forces."
The next communication was _"On the Synthetical Production of Ammonia,
by the Combination of Hydrogen and Nitrogen in Presence of Heated Spongy
Platinum (Preliminary Notice),"_ by G. S. Johnson. Some experiments, in
which pure nitrogen was passed over heated copper containing occluded
hydrogen, suggested to the author the possibility of the formation of
ammonia; only minute traces were formed. On passing, however, a mixture of
pure nitrogen (from ammonium nitrite) and hydrogen over spongy platinum at
a low red heat, abundant evidence was obtained of the synthesis of ammonia.
The gases were passed, before entering the tube containing the platinum,
through a potash bulb containing Nessler reagent, which remained colorless.
On the contrary, the gas issuing from the platinum rapidly turned Nessler
reagent brown, and in a few minutes turned faintly acid litmus solution
blue; the odor of NH_3 was also perceptible. In one experiment 0.0144
gramme of ammonia was formed in two hours and a half. The author promises
further experiment as to the effect of temperature, rate of the gaseous
current, and substitution of palladium for platinum. The author synthesized
some ammonia before the Society with complete success.
The President referred to the synthesis of ammonia from its elements
recently effected by Donkin, and remarked that apparently the ammonia was
formed in much larger quantities by the process proposed by the author of
the present paper.
Mr. Warington suggested that some HCl gas should be simultaneously passed
with the nitrogen and hydrogen, and that the temperature of the spongy
platinum should be kept just below the temperature at which NH_3
dissociates, in order to improve the yield of NH_3.
_"On the Oxidation of Organic Matter in Water"_ by A. Downes. The author
considers that the mere presence of oxygen in contact with the organic
matter has but little oxidizing action unless lowly organisms, as bacteria,
etc. be simultaneously present. Sunlight has apparently considerable
effect in promoting the oxidation of organic matter. The author quotes the
following experiment: A sample of river water was filtered through paper.
It required per 10,000 parts 0.236 oxygen as permanganate. A second portion
was placed in a flask plugged with cotton wool, and exposed to sunlight for
a week; it then required 0.200. A third portion after a week, but excluded
from light, required 0.231. A fourth was boiled for five minutes, plugged,
and then exposed to sunlight for a week; required 0.198. In a second
experiment with well water a similar result was obtained; more organic
matter was oxidized when the organisms had been killed by the addition of
sulphuric acid than when the original water was allowed to stand for an
equal length of time. The author also discusses the statement made by Dr.
Frankland that there is less ground for assuming that the organized and
living matter of sewage is oxidized in a flow of twelve miles of a river
than for assuming that dead organic matter is oxidized in a similar
flow.--_Chem. News._
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