TRANSACTIONS OF THE SECTIONS. 145 



animals became depressed and drowsy. After an interval of four hours, the current 

 was again changed, and the oxygen, purified most carefully of extraneous matter, 

 was a third time given to the animals. It now became more obvious that every 

 animal was under some peculiar depressing influence ; even the rabbit did not escape. 

 The symptoms were entirely different from those arising from carbonic acid. The 

 breathing was quick, but easy and tranquil. There was not the slightest approach 

 to convulsion. The pigeon buried its head under its wing, and simply drooped and 

 slept. The four-footed animals sat witli their four legs straight and their heads 

 between them, nodding as if in profound and pleasant sleep ; they were aroused 

 with difficulty, and fell oil' again in an instant. Then the fore-legs slowly gave way 

 forward, as if paralysed ; and, before the third charge of the oxygen was three parts 

 over, the pigeon was dead, and the kitten was so nearly dead "that it was not easy 

 to detect its chest movement ; the clog gave no sign of sensibility, but breathed 

 softly ; the rabbit was fast asleep. The frogs alone were unaffected. 



At this crisis, a little air was pumped out of the chamber through lime-water ; 

 it gave less indication of carbonic acid than the common air which the experiment- 

 alist was breathing. 



The animals were then removed, and a lighted taper was placed in the chamber. 

 The taper burnt with more brilliancy than in the air, but with a slight yellowness 

 of flame. 



The animals were all nearly dead. The kitten died a few minutes after removal ; 

 the rabbit recovered in two hours ; the dog seemed paralysed in the limbs for the 

 greater part of the clay, but recovered. When the bodies of the pigeon and the kitten 

 were opened, there was found no indication of asphyxia. The lungs were inflated 

 and red ; the heart contained blood on both sides, but the blood in each side was 

 of the same hue, neither being very dark ; the brain was bloodless ; the other organs 

 were natural. The appearances in the pigeon corresponded with these with the 

 most minute accuracy. 



Dr. Richardson next narrated the histories of several other experiments, from 

 which he derived, apparently to demonstration, the following and second major 

 proposition : — Oxygen, when breathed over and over again, although freed entirely 

 from carbonic acid or other known products of respiration, loses its power of sup- 

 porting life; the process of life ceasing, not from the introduction of a poison, but 

 as by a negation, or a withdrawal of some principle extant in the primitive oxygen, 

 which is essential to life. 



The last section of the paper had reference to the influence of oxygen on muscular 

 irritability; and various experiments were again given. On them the author 

 founded the third major proposition. 



Oxygen, while it is essential to muscular irritability and muscular power, exerts 

 its influence over muscle, not as a direct excitant of muscular contraction, but by 

 supplying to the muscle an agent or force by which the muscle is fitted for contrac- 

 tion on the application of an exciting cause. 



The Action of Tea and Alcohols contrasted. By Edward Smith, 3I.D., 

 LL.B., F.R.S., Assistant. Physician to the Hospital for Consumption 

 and Diseases of the Chest, Brompton, Sgc. 



In this paper the author stated the results of a series of original inquiries into 

 the influence of these two substances which appeared in the Philosophical Trans- 

 actions for 1859. 



The general expression of the action of tea is, that it increases all vital actions, 

 and causes the elimination from the body of more material than it supplies. 



It increases the ease, frequency and depth of respiration, but does not much 

 affect pulsation. 



It increases the action of the skin, as shown by the increase of perspiration ; and 

 as in the conversion of fluid into vapour there is a thousand-fold increase in the 

 absorption of latent heat, perspiration must cool the body. 



It increases, and does not disturb, nervous, mental and muscular action, and it 

 is not followed by reaction. 



Small doses often repeated have fourfold the effect of a large dose. 

 1860. 10 



