3b JO URN A L, BOMB A ¥ NA TOR A L BIS TOR Y SOCIETY, Vol. A7 1^. 



I have said above that Atroi)ine checks perspiration and causes dry- 

 ness of skin. But in one case of poisoning, says Schmiedeberg, 

 " the burning hot skin was here and there covered with perspiration 

 (Gerson). The perspiration that comes in this manner has the same 

 origin as that in the death-agony.'* Such sweats, cold and clammy, 

 are the precursors of death. In contrast with this case, it may be 

 noted that Lauder Brunton says that the temperature of the human 

 body is increased by small doses of Atropine and lessened by large 

 ones. 



(9). Action on the Eyfi. — When Atropine is applied topically to only 

 one eye, it dilates the pupil of that eye alone, and not of the other eye. 

 When Atropine acts indirectly,/.^., through the circulation of blood, both 

 the eyes have dilated pupils ; the eye becomes bright, dry, and injected 

 both by topical application and through circulation. " The power of 

 accommodation is lost, and after large doses intraocular accommodation 

 is lost. When Atropine is applied locally so as to affect the pupil of one 

 eye only, the large amount of light entering through the dilated pupil 

 produces contraction of the pupil of the other eye." (Murrell.) The 

 pupil is normally under the control of two antagonistic mechanisms : — 

 (a) The contracting mechanism, reflex in nature, of which the Third 

 Nerve acts as an efferent^ and the Optic Nerve as the afferent tract. 

 {b) The dilating mechanism, tonic in nature, of which the cervical 

 sympathetic nerve is the efferent channel. Murrell says that when 

 the Third Nerve or the Optic Nerve is cut, the pupil dilates from the 

 action of the Sympathetic. When the Sympathetic is cut, the tonic 

 dilating influence ceases, and the pupil contracts. On stimulating the 

 Third Nerve, or the Optic Nerve, the pupil contracts. On stimulating 

 the Sympathetic, the pupil dilates. The dilatation of the pupil produced 

 by the local application of Atropine might, at first sight, be attributed 

 to ]-)aralysis of the Tlnrd Nerve. This view is untenable, says Murrell, 

 for when the Third Nerve is cut and the pupil dilates under the in- 

 fluence of the Sympathetic nerve fibres, the application of Atropine, 

 still further, dilates the pupil. From this it follows that Atropine 

 says Murrell, exerts an action on some local mechanism. This mecha- 

 nism, says Murrell, is probably situated in the Iris^ or in the Choroid^ 

 where ganglionic colls are abundant. The paralysis of accommoda- 

 tion is due to the paralyzing action of Atropine on the Oculo-uiotor 



