588 
FACTS AND OBSERVATIONS. 
HOG CHOLERA IN AMERICA. 
The pathology of this disease has hitherto been ill-under¬ 
stood here, in consequence of the descriptions which have been 
forwarded being so vague, besides, as a rule, being furnished by 
non-medical correspondents. We find now, however, from the 
information afforded by Dr. Harris, Sanitary Superintendent 
the New York Board of Health, that the malady is identical 
with the one known in Great Britain as typhus, and in 
Ireland as the Hue disease^"" or red soldier^'" vidgo. A 
few years since this malady destroyed large numbers of pigs 
in nearly every county in England, neither age, breed, nor 
condition affording any immunity against the attack. 
Alluding to this subject a few months ago, we drew atten¬ 
tion to the circumstance of Dr. W. Budd having published a 
most elaborate paper upon the disease, which was reproduced 
in our pages from the Journal of the Royal Agricultural 
Society. Isolated cases of the malady have only recently been 
met with in England, which have proved more amenable to 
treatment. During the epiozootic prevalence of the malady 
medicinal agents availed but little. The sulphites, however, 
were found to he among the most useful agents. 
Facts and Observations. 
The Chemistry of Nitro-glycerin. —M. Tilbero: has 
made some researches on this substance, making use of the 
nitroglycerine manufactured on the large scale at Stockholm. 
This material is decomposed by potassa, giving rise to the 
formation of nitrate of potassa and glycerine; but, at the 
same time, there are formed secondary products, as ammonia, 
cyanogen, oxalic and ulmic acids, and nitrous acid. Accord¬ 
ing to the results of elementary analysis made by the author, 
the formula for this kind of nitroglycerine should be 
C3H5(NO-)303. The substance is soluble in concenFrated 
sulphuric acid, yielding a clear solution, and forming a 
sulphoconjugate which, on being combined with bases, gives 
crystallisable salts .—Chernical Neivs. 
The Constitution of the Coal-tar Gases is the 
title of a paper some time since read before the Vienna 
Academy by Herr Tulsowski. His observations tend to 
prove that the entire series of these basic substances, with 
their numerous derivatives, taking their origin most probably 
