CIRCULATORY AND LYMPHATIC SYSTEMS 297 



466. The lands principally affected are poor, undrained, shivery 

 gravelly pastures, and sour, wet mosses where the herbage is of a 

 coarse, acrimonious nature, in which acrid plants such as tormentil 

 abound. The malady generally makes its appearance in the summer 

 and autumn months — August and September especially — following, 

 usually, a sharp, heavy rain after a spell of dry weather, when the 

 grasses spring up rapidly, and, under these conditions, the complaint 

 is rife. Cattle bred and reared on the above-mentioned soils are, 

 however, more immune from attack than those reared on good land, 

 and brought on to the bad to graze. I am strongly of opinion that 

 the disease is due to a want of a normal quantity of saline matters in 

 the food, which, in turn, interferes with and destroys the balance 

 between the solids and fluids of the blood. As already shown, blood 

 contains a large proportion of salt, and has, in fact, a soft saline taste. 

 Now, on account of the acid nature of the food obtainable on these 

 sour pastures, a sufficient amount of saline material is not conveyed 

 to the blood to preserve the equilibrium between the solid and fluid 

 parts, so that the watery portions, by endosmosis, pass through the 

 cell walls of the red corpuscles, and so distend them that they burst, 

 and they then pass through the excreting water tubes — uriniferous 

 tubes — of the kidneys into the urine, accompanied by the colouring 

 matter of the blood, which they have thus liberated, giving to it the 

 red colour noted, and instituting the name of the disease. 



467. Of late a great deal has been published respecting the tick 

 Ixodes ricinus being the cause of red-water in cattle. This may be the 

 case in foreign countries, and the disease carried from one animal to 

 another by means of the tick, but I must say that of all the 

 cases I have seen — and they have been no small number — I have 

 only on four occasions seen ticks on cows affected with red- water, and 

 at the same time other cattle going with them ailed nothing, although 

 they also had ticks on their bodies. The most of my cases have been 

 on poor, badly drained, shivery, gravelly pastures, or on sour, wet, 

 low-lying, undrained mosses, where the herbage was of a rank, sour 

 character, and these particular pastures have been situated in the 

 midst of well-drained, highly cultivated lands, on which cattle in 



