308 BROMIDES 



and diastase, is a valuable tonic and restorative for weakly, 

 unthrifty foals and puppies, in doses of 3Jv. to ij. per day. 



BROMINE AND BROMIDES 



BROMINE. BROMUM. A liquid, non-metallic element ob- 

 tained from sea- water, and from some saline springs. 

 (Not official.) 



BROMIDE OF POTASSIUM. POTASSII BROMIDUM. KBr. (B.P.) 



Bromine, like its analogues chlorine and iodine, has a 

 great affinity for hydrogen, removes it from its several com- 

 binations, and hence is antiseptic and indirectly an oxidising 

 agent. It is very diffusible. These three halogens are anti- 

 septic, disinfectant, and topically irritant and stimulant. 



BROMINE is a dark, red-brown, volatile liquid, has a strong 

 disagreeable odour and taste, and produces a yellow colour 

 when added to cold solution of starch : soluble in thirty 

 parts of water. It is occasionally used as a caustic in malig- 

 nant and fungoid diseases, one part being dissolved in ten to 

 fifteen parts of rectified spirit. Diluted Hydrobromie Acid 

 containing ten per cent, by weight of hydrogen bromide, is 

 devoid of irritant action, and is occasionally prescribed as a 

 nerve sedative, but is not so convenient or effectual as 

 potassium bromide. 



THE BROMIDES, including those of potassium, sodium, and 

 ammonium, do not differ materially in their action. They 

 have very slight topical effect on the skin or mucous surfaces, 

 but are rapidly absorbed, and readily decomposed, the potas- 

 sium bromide forming in the stomach sodium bromide and 

 potassium chloride. They are quickly eliminated by all the 

 excreting channels, chiefly by the kidneys, but also to some 

 extent in the milk, sweat, and from the lungs. Large doses 

 act as depressants of the spinal cord and reflex portions of the 

 brain, impairing afferent conductivity of nerves. They are 

 devoid of true hypnotic action, such as that of chloral 

 hydrate, but diminish cerebral excitability by reducing the 

 activity of the reflex parts of the brain. 



POTASSIUM BROMIDE is the salt in general use. It is pre- 

 pared by heating bromine and caustic potash with charcoal, 

 and contains 67 per cent, of bromine. It occurs in colourless, 



