BIOLOGY. 289 



properties of brucia, thebaia, and codeia are immensely dimin- 

 ished by the addition of methyl ; and that the bodies produced, 

 instead of being, as all three of these alkaloids are, strongly con- 

 vulsent, possess, on the contrary, the physiological action of cu- 

 rare. Morphia, as is well known, possesses both soporific and 

 convulsent properties; its toxic action is much diminished by tho 

 addition of iodide of methyl ; its convulsent action is destroyed, 

 but its soporific action remains. 



PHYSIOLOGICAL AND THERAPEUTICAL ACTION OF CAFFEIN. 



The "Archives de Physiologic " for Jan. -Feb., 1868, contains 

 a paper on this subject, by Dr. M. Leven. The following are the 

 conclusions he draws from his experiments : — 



Cafi"ein appears to directly stimulate the heart. When first 

 absorbed the circulation and respiration are accelerated, the 

 I^ulse is more frequent and firmer, and the secretions more active. 



The central nervous system, the brain and spinal cord, and the 

 nerves are stimulated. 



The muscular system of the life of relation and that of organic 

 life contract violently. 



The muscles of the former system are affected with trembling 

 or with general contraction. The fibres of the stomach, of the 

 intestines, and of the bladder also contract. 



At a later period after absorption of caflfein, the action of the 

 heart is lessened ; the frequency and firmness of the pulse dimin- 

 ished ; the muscular system becomes exhausted, but is not para- 

 lyzed. The nervous system also sufi'ers exhaustion. 



Caffein does not entirely extinguish reflex action, nor the func- 

 tions of nerves and muscles. 



It acts as a poison on different animals in different doses ; it 

 may be given to man in the dose of many grammes without in- 

 jury. 



It is readily eliminated from the system, and remains in it only 

 a few hours. 



He further states that caffein, like alcohol, diminishes the secre- 

 tion of urea, but increases the quantity of urine excreted. It di- 

 minishes the waste of the organs, and economizes the tissues. 



With two litres of coffee daily, the Belgian miners undergo, 

 without substantial food, excessive muscular exertion. The cara- 

 vans which traverse the desert are supported by coffee during long 

 journeys and lengthened privation of food. It is known that 

 some old persons are almost exclusively nourished by coffee. — 

 Am. Jour, of Med. Sciences. 



APHASIA.' 



According to Dr. Fabre, of Marseilles, a fourfold division is 

 made of this disease. In the first variety or degree the patient 

 forgets words ; in the second, he loses voluntary control over their 

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