ARSENICAL SOLUTIONS 283 



sunny weather. On no account should sheep be returned to 

 their grazings until they are dry, and there is no risk of their 

 poisoning the pastures. 



DOSES, etc. Of Arsenic. Horses and cattle take grs. ij. to 

 grs. x. ; sheep, gr. j. to grs. ij. ; and dogs, gr. T ] K to gr. T ^. 

 When it is desired to produce local action on the stomach 

 and intestines, small doses are given before food ; when its 

 absorption is required, it is administered immediately after 

 meals. It is usually given once daily, and continued for a 

 week or ten days, when a change of prescription is often 

 desirable. When it causes acceleration or hardness of the 

 pulse, injection of the conjunctiva, indigestion, diarrhoea, or 

 other physiological action, the drug should be discontinued, 

 or the dose materially reduced. 



It is most active and uniform in its effects when prescribed 

 in solution with diluted acid or alkali. The Liquor Arsenici 

 hydroehlorieus contains one grain of arsenic in 110 minims. 

 Liquor Arsenicalis or Fowler's solution made with arsenious 

 anhydride, potassium carbonate, compound tincture of 

 lavender and distilled water is the preparation most fre- 

 quently used in veterinary practice. It contains one grain 

 of arsenic in 110 minims or about 4J grains to the ounce. 

 The dose for horses and cattle is from half an ounce to an 

 ounce and a half. Dogs may be given 2 to 10 minims. 



The Liquor Arsenii et Hydrargyri lodidi or Donovan's 

 solution, of which 1 10 minims correspond to one grain each 

 of arsenious iodide and mercuric iodide, is useful in chronic 

 skin and rheumatic complaints. The dose for horses and 

 cattle is ^iv. to j. Arsenical preparations are frequently 

 administered in the drinking water, or in the mash. For 

 hypodermic or intra-tracheal injection minimum doses of 

 Fowler's solution diluted with two parts of distilled water 

 may be prescribed. 



Cacodylic acid (Dimethyl arsenic acid, AsO(CH 3 ) 2 HO) is an 

 arsenical compound in which the arsenic is in organic com- 

 bination. It contains 54 per cent, of arsenium. It is a white 

 crystalline substance, soluble in four parts of alcohol, and 

 readily soluble in water. Its salts, cacodylate of soda or 

 sodium dimethylarsenate, which is very soluble in water 

 and cacodylate of iron, have been employed in the treatment 



