342 
NA TORE 
[Han 27, 1870 
smoke-like appearance as that obtained with a flame is observed. 
In short, the cotton wool, when used in sufficient quantity, 
completely intercepts the floating matter on its way to the lungs. 
And here we have revealed to us the true philosophy of a 
practice followed by medical men, more from instinct than from 
actual knowledge. In a contagious atmosphere the physician 
places a handkerchief to his mouth and inhales through it. In 
doing so he unconsciously holds back the dirt and germs of the 
air. If the poison were a gas it would not be thus intercepted. 
On showing this experiment with the cotton wool to Dr. Bence 
Jones, he immediately repeated it with a silk handkerchief. The 
result was substantially the same, though, as might be expected, 
the wool is by far the surest filter. The application of these ex- 
periments is obvious. If a physician wishes to hold back from 
the lungs of his patient, or from his own, the germs by which 
contagious disease is said to be propagated, he will employ a 
cotton-wool respirator. After the revelations of this evening 
such respirators must, I think, come into general use as a defence 
against contagion. In the crowded dwellings of the London 
poor, where the isolation of the sick is difficult, if not impossible, 
the noxious air around the patient may, by this simple means, 
be restored to practical purity. Thus filtered, attendants may 
breathe the air unharmed. In all probability the protection of 
the lungs will be protection of the entire system. For it is ex- 
ceedingly probable that the germs which lodge in the air- 
passages, and which, at their leisure, can work their way across 
the mucous membrane, are those which sow in the body epi- 
demic disease. If this be so, then disease can certainly be 
warded off by filters of cotton wool, T should be most willing 
to test their efficacy in my own person, And time will decide 
whether in lung diseases also the woollen respirator cannot abate 
irritation, if not arrest decay. By its means, so far as the germs 
are concerned, the air of the highest Alps may be brought into 
the chamber of the inyalid. Joun TYNDALL 
SCIENTIFIC SERIALS 
THE Zeitschrift fiir Chemie (No. 1) contains an account of 
some unfinished experiments by Muck on manganous sulphide, 
and a note by Dr. Baumhauer, of Bonn, on the action of aqueous 
hydric chloride on nitrobenzol. Inthe latter of these the 
author points out the interesting fact that dichloraniline is a 
principal product of the reaction, Robert Otto communicates 
several papers containing the results of experiments which he 
has performed, for the most part, with the co-operation of 
Ikugen Dreher. The subjects of the papers are ‘* Mercuric 
Diphenyl,” under which title a. tolerably exhaustive account of 
this body is given; ‘‘Mercuric Ditolyl,” which was not so 
extensively examined ; “* Onthe deportment of Dibenzyl at a high 
temperature ” (it splits into Toluol and Toluylene) ; ‘*On the 
transformation of hydro-phenylic sulphide into phenylic 
sulphide” (the mercuric derivative decomposes thus at 180° :— 
(CgH;)2HeS, = (CgH5)o5. + Hg); *fOn mercuric dinaphtyl,” 
from which it appears that the presence of ethylic acetate 1s very 
advantageous in the usual mixture whereby the body is prepared ; 
“On mono-ethylic and mono-methylic mercuric acetate ;” and 
“On the preparation of organic sulphur-compounds by means 
of sodic hyposulphite.”—A. Geuther contributes a short article 
“On the volatile acids of croton oil.” He finds that the oil 
contains no crotonic acid, which name is consequently a misnomer. 
Of the two metamers, C,H,O., he consequently designates the 
solid modification ¢etranylic, and the liquid variety guartenylic 
acid. Croton oil contains a metamer of angelic acid, for which 
the author proposes the name ¢ig/imic acid. —Markownikoff finds 
that the butylic (fermentation) alcohol, when transformed into 
iodide, and then, by alcoholic potash, into olefiant, furnishes 
with hydric iodide the tertiary pseudo-butylic iodide.—Petrieff 
describes so/id azoxytoluide (fusing at 57°). 
Tue Annales de Chimie et de Physique for December last con- 
tains a short note by M. Soliel on an ocular micrometer, the 
principle of which was discovered independently by Prof. Govi 
and himself. The rest of the number is wholly occupied by 
abstracts of foreign scientific papers. 
Tue Annals and Magazine of Natural History, fourth series, 
No. 25. The January number of this journal contains the con- 
clusion of Mr. Wollaston’s descriptions of the Coleoptera of St. 
Helena, to which we shall refer elsewhere. Mr. D. Sharp also 
publishes a paper on the species of PAilhydrus found in the 
Atlantic Islands, which may be regarded as supplementary to 
and rectificatory of Mr. Wollaston’s works on the Coleoptera of 
those islands. Dr. Lycett describes a byssiferous fossil 7yigonta 
(7. carniata Ag.) Messrs. A. Hancock and R. Howse describe 
in considerable detail the remains of a fossil fish (Yanassa 
bituminosa Schloth,) from the Permian marl-slate of Midderidge 
in the county of Durham. They identify with the genus 
Fanassa the coal-measure form described by Messrs. Hancock 
and Atthey under the name of Climaxodus lingueformis, and 
regard the genus as belonging to the Rays, and probably allied 
to Myliobates. The known specimens consist chiefly of the teeth, 
which were originally described by Schlotheim as Trilobites, under 
the name of 7. dituwminosus; different examples have been 
described as fish-remains under various names, and the authors 
refer to their species the Faxassa angulata, Humboldti, bitumi- 
nosa, and dictea, Dictea striata and Byzenos latipinnatus of 
Count Miinster, and the Acrodus larva of Professor Agassiz. 
This paper is illustrated with two excellent plates. Dr. Carl 
Semper describes the //edix inequalis (Pfeiff.) from Australia as 
forming a new genus of Testacellidae, to which he gives the name 
of Rhytida. Professor E. Perceval Wright describes and figures 
a new parasitic Crustacean, Pennella orthagorisct, obtained from 
a sun-fish in Cork Harbour; and Mr. John Gould describes a 
new Pigeon, Ot#diphaps nobilis, forming the type of a new genus. 
—The only botanical paper in the number is the thirty-first 
instalment of the Rey. W. A. Leighton’s ‘* Notulee Lichenolo- 
gicee,” containing an analytical examination of certain new 
characters in the species of the genera Vephroma and Vephro- 
mium.—Besides the translations and abstracts of foreign papers 
which appear among the miscellaneous contributions, this number 
contains the first part of a translation of Professor Hackel’s 
memoir on the organisation of sponges, and their relationship 
to corals, in which the author maintains that the corals (4stho- 
zoa) are very nearly related to the Sponges, that the latter belong 
to the great group of the Ccelenterata, and that ‘the sole mor- 
phological character which sharply and decidedly separates” 
them from the rest of the Ccelenterata is to be found in the 
‘deficiency of the urticating organs in all sponges.” 
THE Montteur Scientifique for January Ist has much of its 
space occupied by an account of the legal inquiry resulting from 
the remarkable explosion of potassic picrate which occurred in 
the Place de la Sorbonne on the 16th June last. The evidence 
and the speeches of counsel are.given at considerable length. 
M, Dubrun{fant contributes an article on the Saline Analysis of 
Sugars, and on Melassimetry. There is also the usual account 
of the sittings of the Academy of Sciences; a Photographic 
Review, and a review of foreign journals—both very carefully 
written, A new feature in this serial, introduced this year, is a 
price-current of the principal products referred to in the papers 
it contains, and for the general use of subscribers. We cannot, 
however, help thinking that our able contemporary, in seeking 
to oblige its readers, has undertaken a task which, from the 
smallness of available space, it cannot adequately fulfil. A full 
price-current ought to have a periodical to itself, 
Revue des Cours Scientifiques, January 22.—The first paper 
consists of extracts from an eloquent obituary notice of Trousseau, 
read by M. J. Bechard, the Secretary of the French Academy of 
Medicine, at the recent annual general meeting. ‘‘In this cogy 
of the man who is one of the most distinguished personifications 
of the old empirical medicine, M. Béchard has skilfully contrived 
to afford us a glimpse of the advent—possibly close at hand—of 
scientific medicine.” A lecture by M. Lortet on the physio- 
logical effects of mountain climbing is the second paper in the 
present number of the Aevwe. We hope shortly to lay before 
our readers a full account of M. Lortet’s observations. The 
other papers are one by Prof. Mayer, of Heilbronn, the recently 
elected Corresponding Member of the Institute of France, on the 
necessary consequences and inconsequences of the mechanical 
theory of heat, and a communication, Jately presented to the 
Academy of Sciences, by M. St. Claire Deville, on the nascent 
state of bodies. 
THe American Naturalist—In the number for the present 
month there is an original article on the microscopic exami- 
nation of shavings, and two others on the birds of Massachusetts ; 
likewise a continuation of a review of Professor Huxley’s Classi- 
fication of Animals, in which the opinion is expressed that the 
publication of that book will not endanger the Cuvierian system. 
A reprint is also given from the Popular Science Review of the 
temperate and well-written article in which Prof, Cleland, of 
Glasgow, once more lays the ghost of phrenology, and gives, in a 
popular way, much solid information. 
