THE FATE OF ARSENIC IN THE BODY., 65 1 



horse was dosed with i gm. of the powder, and another with 

 2 gm. of the powder, every day for a fortnight without being 

 any the worse for it. Another liorse received 4 gms. daily and 

 died by the time 24 gms. had been administered. A fourth re- 

 ceived 5 gms. twice weekly and died after the fourth dose. 



It seems not improbable that moderately large doses 

 repeated daily would be more toxic than the same total amount 

 administered in one big dose, since b\- repeated administration 

 the alimentary tract would be afforded no opportunity of freeing 

 itself from the slowdy soluble powder. This, of course, would 

 not hold for repeated administrations of definitely sub-toxic doses 

 either of arsenious oxide or sodium arsenite, and the question of 

 " acquired tolerance "would then enter. 



In experimental work on sheej) {/. c, i) it was found that 

 death was uncertain with anything less than 0.5 gm. As^O, as 

 arsenite ( 10 mg. per kilo) administered orally, or 0.3 gm. (6 

 mgs. per kilo) intrajugularly. In most cases 0.2 gm.-o.3 gm. is 

 safe by the mouth (5 mg. per kilo), and as the experience with 

 "wire-worm remedy" shows, o.i gm. (2-3 mg. per kilo) can be 

 safely adimnistered medicinally in dosing flocks against hccmou- 

 chus conforfjis. 



0.1 gm. has been injected intrajugularly in over half a dozen 

 different cases without symptoms of intoxication being shown. 

 and three sheep were injected with 0.2 gm. without disaster. 0.3 

 gm. injected intrajugularly was rapidly fatal in tAvo cases, but 

 non-fatal in a third, although symptoms of intoxication were 

 5hov;n. 



From the limited data at disposal for cattle, i gm. (2 mg. 

 per kilo) appears moderately safe by iiUrajugular injection while 

 2 gm. is uncertain — some animals tolerating it and others suc- 

 cumbing on the day of injection. Effects of oral administration 

 of soluble arsenic are more erratic with cattle, owing partly to 

 idiosyncrasy and partly to the fact that tlie dose may pass direct 

 to the abomasum in one case and indirectly through the rumen in 

 another. In the former case the arsenic reaches the intestine 

 sooner and is more rapidly absorbed ; in the latter the dose may 

 be diluted down in the rumen and passed on for absorption much 

 more slowly. 



Veterinary Research Laboratories, 

 Pretoria. 



National Chemical. Service. — Mr. Kenneth B. 



Quinan. C.H.. of the Cape Explosives Works. Somerset V/est, 

 C.P.. has recently received the following letter from Sir Herbert 

 Jackson, K.B.E.. F.R.S.. President, and Mr. R. B. Pilcher, 

 F.C.I. S., Registrar and Secretary, representing the Institute of 

 Chemistry : — 



On behalf of the Fellows and Associates of the Institute of Chemistry 

 of Great Britain and Ireland, we desire to convey to you an expression 

 of high appreciation of your valuable services to the British Empire and 

 to the Allies during the Great War. 



