104 Scientific Intelligence. 
preservation of wood, sugar, distillation, gelatine, paper, illuminating gas, 
heating by gas, wn bituminous c &e. 
P éclet— Nouveaux seinen relatifs au chauffage, 1 vol. 4to. with 
plates.—This ares which follows the great work of Péclet entitled 
“ Traite de la Chaleur,” relates especially to the heating and ventilation 
of public establishments, as hospitals and prisons e find here interest- 
ing details in regard to the heating of the ae of en of the Institute 
and of the celebrated glassworks of Bacc There are also the usual 
formulas in omnes to cooling and the (eee of bea through dif- 
ferent bod 
Payen able Substances Alimentaires.—A small 12mo. treating of the 
methods of improving alimentary rose of preserving them, and 
also of detecting their adulteration. This is a synopsis of the course of 
public lectures by Payen vi 6 Conservatoire des Arts et Métiers, deliv- 
ered by request of the gove 
Heuzé.—Les Plantes Indatrcies, 2 vols. 8vo.—This work follows 
a treatise on sia by the same author, which we have already men- 
tioned. The new work treats of the culture of plants which furnish the 
food of Parent and such as are used in the arts. Tome I treats 
oleaginous a tinetorial plants, saliferous plants, and those used 
as condiments, Tome II is devoted to textile, narcotic, te and 
medicinal silentn "and plants which greats sugar and alco 
SCIENTIFIC INTELLIGENCE. 
_ I, PHYSICS AND CHEMISTRY. 
Agee ,' 
(1.) On the propagation of heat in gases.—Macwvs has communicated 
to the Royal Academy at Berlin, a memoir on the propagation of heat 
in gaseous media, the principal results of which are as follows 
1, The temperature which a thermometer finally assumes in a space 
which is a from above is different when this space is filled with 
different gase 
2. This tanuipers Bird is higher in hydrogen than in any other gas 
3. The temperature is also higher in this gas than in a and the 
greater the density of the gas, the higher is the Ss es 
4, Hydrogen therefore pa, pa heat like the metals, 
5. In all other gases, the temperature which the thermometer finally 
assumes, is lower Shan i in eh and the more dense the gas employed, 
the lower is the temperatur 
6. We must not cere conclude from this that gases do not conduct 
heat, but only that they do this to so small an extent that the action of 
the conduction is SORES by the resistance which they oppose to 
the passage of hea 
7. The Snethebis conducting power of hydrogen i is shown not only 
when this is freely moveable but so when it is contained between pieces 
of eter or any other substance of a loose texture which prevents 
its mot 
gases, hydrogen included, offer resistance to the passage of rays 
of heat, and and the more extended they are, the greater is this resistance. 
