288 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



us of the human body, as the brain is known to contain a 

 considerable amount of phosphorus, while sulphur exists in 

 the liver, and an alkaline solution is in circulation between 

 them. He took a frog, and, having secured anaesthesia by 

 the application of chloroform, an incision was made through 

 the abdominal walls in the right hypochondriac region, and 

 a copper wire passed into the substance of the liver. The 

 eyeball was then pierced, and a similar piece of copper wire 

 brought in contact with the brain by passing it through the 

 optic foramen. The free extremities of the copper wires 

 were then brought in contact with the exposed sciatic nerve 

 of another frog's hind leg, when powerful convulsions were 

 immediately induced in the muscles. 



Fortified by this experiment, Mr. Gray thinks that a por- 

 tion, at least, of this current is generated by the action of the 

 alkaline fluid on the sulphur and phosphorus contained in the 

 organs mentioned. Although the living body is known to 

 have other sources of electricity, Mr. Gray thinks that the 

 prime agent in nervo-motor power is derived from the reac- 

 tion of the brain and liver, especially in view of the fact that 

 the kidneys excrete about 72 grains per diem of phosphoric 

 acid, and of sulphuric acid nearly 100 grains are produced 

 per diem, chiefly from the brain and liver. 



Mr. Gray also thinks that the sympathetic nerve, with its 

 branches and ganglia, is not a separate or isolated system, 

 but merely a constituent part of the general nervous system, 

 having the function of regulating the movements of involun- 

 tary muscular fibre, and obtaining its nerve force from the 

 brain. An arrangement similar to that of the Leyden jar is 

 suggested, as occurring in the membranes inclosing the vis- 

 cera, the lungs, the heart, and the great serous cavities of the 

 body. 18 A, December 15, 1871, 317. 



MENTAL CHARACTERISTICS OF LOWER ANIMALS. 



Dr. W. Lauder Lindsay, an eminent physician, in charge of 

 the Royal Insane Institution at Perth, has lately published 

 some interesting articles upon 'the mental characteristics of 

 the lower animals, in which, as the result of long-continued 

 investigations prosecuted by him, he takes the ground, first, 

 that certain of the lower animals possess minds of the same 

 nature as that of man; second, that there is no essential 



