AGRICULTURAL TEXT-BOOK. 23 



water drawn fresh from the well will make the coat of a horse 

 unaccustomed to it stare: and it will not unfrequently gripe 

 and otherwise injure him. (Youatt.) Milk, I utter, and cheese 

 are also sensibly affected by the quality of the water drunk by 

 the cow. Dr. Wilson has found fluoride of calcium in milk, as 

 well as in the blood and urine of animals, which must have been 

 derived from this substance dissolved in the water usually drunk. 

 (Proc. British Assoc.) 



69. Goitre and Cretinism, diseases common in the vallies of 

 the Alps, as well as in the other parts of the world, are believ 

 ed to arise from the deleterious action of the water containing 

 salts of magnesia, and the absence of a sufficient quantity of 

 lime. In some places cattle are subject to a disease of the bones 

 in consequence of a want of lime in the water. On the contra 

 ry, carbonic acid acts favorably on vegetable life. Dr. Daubeny 

 found by experiments, that although very large quantities of 

 carbonic acid were injurious to plants, yet that when present in. 

 water, from one to five per cent more than is natural, it is bene 

 ficial 



70. M. Lassaigne has found arsenic present in the natural 

 deposites of the mineral waters of Wattviller to the amount of 

 2.8 per cent.; but the poisonous property of the arsenic is de 

 stroyed by its combination with peroxide of iron. Free sulphuric 

 acid has also been detected in springs in Virginia. 



71. River water differs much in its constituents from spring 

 water. It takes its character from the geological formations 

 through which it flows. It is apt to hold in suspension much 

 sand, earth, and organic matter. The quantity of sediment dis 

 charged by the Mississippi River annually is estimated at from 

 2,137,061,974 cubic feet (Marr) to 28,188,083,892 cubic feet 

 (Brown and Dickeson.) 



