66 PATHOLOGY AND GENERAL TREATMENT OF CATTLE. 
minds, and to those scientific inquiries which will be the means 
of increasing the value of their land and its produce. The works 
of Professors Daubeny and Liebig now form a part of the library 
of the farmer, as they ought of the veterinarian. Natural history 
will form also a pleasing study ; “ the investigation of the different 
tribes of insects,” the habits of the numerous aphides, so multi- 
fariously distributed, and none more successful in blighting the 
prospects of the crops of the farmer — these will add also a pleas- 
ing and profitable link to our profession ; for, be it remembered, 
we should stand as high in the estimation of the agriculturist, by 
finding a remedy for the destruction or prevention of this insectile 
tribe, as we should for the discovery or the cure of disease af- 
fecting his stock. It will be occupying too much space to en- 
ter into a thorough detail of the genera aphides here, but suffi- 
cient history can be gathered from the authors on entomo- 
logy, and in the quarterly volumes of the Royal Agricultural 
Society. Next comes geology in connexion with agriculture, 
which initiates us into the different surfaces and subsoils, while 
chemistry gives us the component parts, some of which may be 
rich in the production of nitrogen, and possess high powers of 
fertilizing, causing, under certain atmospherical circumstances, a 
rapid development of growth ; and the different kinds of grasses, 
or staminiferous herbage, then become charged with azote or am- 
monia, known by its deep green hue or tinge. Cattle and sheep, 
when depasturing on these, will begin to have their secretions 
increased, and assimilate the nitrogeneous principle, and convert 
it into fat : but such soils, as is too often the case, particularly 
meadows near towns, are surcharged with the products for the 
formation of ammonia ; and cattle and sheep, when turned into 
them, are frequently found dead from apoplexy, paralysis, or 
congestion. On the other hand, the absence of the alkaligene- 
ous principle, as an active agent in some soils, is a cause of dis- 
ease, from not furnishing material enough for the constituents 
of the animal frame. 
This is a beautiful range for philosophical inquiry, and will 
ultimately prove that the most part of our diseases in cattle are 
caused by a limited range in depasturation, and that scarcely 
any disease would arise, if uncontrolled by the boundary of man. 
Domestication and art doom them to unnatural disease, which 
remains for us to combat. Excess and want of the vital principle 
of vegetation are both causes of disease in animals. This leads 
me to the aptitude that several soils have in the production of dis- 
order in our stock. I am well acquainted with several farms 
in which red-water is prevalent at certain months in the year; 
and, from remarks which I have made on this complaint, con- 
