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climate, so constantly associated with wet lauds, are universally 

 charged with causing the disease. These act on the animal body to 

 produce a lymphatic constitution with an excess of connective tissue, 

 bones, and muscles of coarse open texture, thick skins and gummy legs 

 covered with a profusion of long hair. Heuce the heavy horses of Bel- 

 gium and southwestern France have suffered severely from the affec- 

 tion, while high dry lands adjacent, like Catalonia in Spain, and Dauph- 

 iny, Provence, and Languedoc, in France, have in the main escaped. 



The rank aqueous fodders grown on such soils are other causes, but 

 these again are calculated to undermine the characters of the nerv- 

 ous and sanguineous temperament, and to superinduce the lymphatic. 

 Other foods act by leading to constipation and other disorders of the 

 digestive organs, thus impairing the general health ; heuce in any ani- 

 mal predisposed to this disease, heating, starchy foods, such as maize, 

 wheat, and buckwheat are to be carefully avoided. It has been widely 

 charged that beans, peas, vetches, and other leguminosa are dangerous, 

 but a fuller inquiry contradicts this. If these are well grown they in- 

 vigorate and fortify the system, while like any other fodder if grown 

 rank, aqneous, and deficient in assimilable principles they tend to lower 

 the health and open the way for the disease. 



The period of dentition and training is a fertile exciting cause, for 

 though the malady may appear at any time from birth to old age, yet 

 the great majority of victims are from two to six years old, and if a 

 horse escapes the affection till after six there is a reasonable hope that 

 he will continue to resist it. The irritation about the head during the 

 eruption of the teeth, and while fr.etting in the unwonted bridle and 

 collar, the stimulating grain diet and the close air of the stable all com- 

 bine to rouse the latent tendency to disease in the eye, while direct 

 injuries by bridle, whip, or hay-seeds are not without their influence. 



In the same way local irritants like dust, severe rain and snow- 

 storms, smoke and acrid vapors are contributing causes. 



It is evident, however, that no one of these is sufficient of itself to 

 produce the disease, and it has been alleged that the true cause is a 

 microbe, or the irritant products of a microbe, which is harbored in the 

 marshy soil. The prevalence of the disease on the same damp soils 

 which produce ague in man and anthrax in cattle has been quoted in 

 su])port of this doctrine, as also the fact that the malady is always 

 more prevalent cwteris paribus in basins surrounded by hills where 

 the air is still and such products are concentrated, and that a forest or 

 simple belt of trees will, as in ague, at times limit the area of its prev- 

 alence. Another argument for the same view is found in the fact that 

 on certain farms irrigated by town sewage this malady has become 

 extremely prevalent, the sewage being assumed to form a suitable 

 nidus for the growth of the germ. But on these sewage farms a fresh 

 crop may be cut every fortnight, and the product is precisely that aque- 

 ous material which contributes to a lymphatic structure and a low tone 



