EFFECTS OF TOBACCO. 105 



expressed juice yields, beside these, woody fibre, oxalate and phos- 

 phate of lime, with oxide of iron and silica in the ashes. The manu- 

 factured tobacco yields, in addition to these, carbonate of ammonia, 

 and chloride of calcium, produced probably by the salammonic used 

 to give it pungency. Nicotina, a volatile alkali, exists in the leaves 

 roots and seeds. It acts as a narcotic poison on insects ; it is inflam- 

 able and has an acrid and burning taste. The concrete volatile oil of 

 tobacco is obtained by submitting the leaves with water to distillation. 

 6 Ibs. of leaves yield 11 grains of oil, swimming on the surface of the 

 liquid. The oil is a solid, soluble in ether and caustic potash. The 

 empyreumatic oil of tobacco is scarcely distinguished from that of the 

 fox-glove. Tobacco smoke is composed of carbonate and acetate of 

 ammonia, nicotianin, empyreumatic oil, soot, moisture, &c. Several 

 gases, water, oil and resin, with several acids, are obtained by the 

 distillation of tobacco. 



The physiological effects on carnivorous animals, are nausea, vomit- 

 ing, sometimes purging, trembling, staggering, convulsive movements, 

 and stupor. 5 drachms of rappee introduced into the stomach of a 

 dog, secured by a ligature on the aesophagus, caused death in 9 hours, 

 and 2 drachms applied to a wound killed one in an hour. An infusion, 

 thrown into the rectum paralysed the heart, and death ensued in a few 

 minutes. Its effect on the heart is through the nervous system, solely. 

 The effects on the herbivora, as with other poisons, are less marked. 

 4 ounces given to a horse produced no very remarkable effects. 



The effects on man are a sensation of heat in the throat and stomach, 

 nausea, and a peculiar giddiness. It is thought to promote absorp- 

 tion, as dropsical swellings often disappear by the use of it. In larger 

 doses i-t produces a distressing sensation at the stomach, cold sweat, 

 enfeebled vision, laborious breathing, &c. ; and in excessive doses, be- 

 side these effects, convulsions, paralysis, and death. Taken as snuff, 

 it blunts the sense, alters the tone of the voice, and sometimes causes 

 dispepsia, &c. Smoking produces similar effects. With moderate 

 smokers thirst is induced by the increased secretion of saliva. It 

 tranquilizes the mind, and hence its general use. Some medical wri- 

 ters say that they know no ill effects arising from the practice, while 

 others describe many. As a prophylactic against contagous or epi- 

 demic diseases, it is believed to have no special virtues, as has been. 

 supposed. Chewing is attended with effects like those above no- 

 ticed. 



The operation of tobacco is like that of Lobelia in/lota ; it also agrees 

 with foxglove in enfeebling the action of the vascular system, though 

 much inferior in its power. It promotes secretions, and relaxes the 

 muscular fibre. It differs from beladona and stramonium, and is 

 thought by some to produce effects not unlike those of aconite. Its 

 effects in relaxing the muscular fibre renders it a valuable antispas- 



