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438 REPORTS ON tSr statk of science. 



apparatus litis been de\i£ed for the oxygen analysis of samples of 

 10 cubic centimetres each. The apparatus used has involved the elabo- 

 ration of the ' capillary method ' of gas analysis. 



II.— The Results obtained in Individual Organs. 



The following organs have been investigated by the Committee : — 



The heart, the kidneys, the salivary glands, the pancreas, the 

 intestines, and to some extent muscle. In addition to these a few 

 preliminary experiments have been undertaken on the liver. 



The Heart. — The amount of oxygen taken up by the heart varies 

 with the activity of the organ. Adrenalin, atropine, and barium 

 chloride increase the oxygen intake of the heart ; stimulation of the 

 vagus or administration of pilocarpine, chloroform, or potassium chloride 

 reduces the quantity of oxygen which the heart requires. 



The Salivary Cllamh. — The oxygen exchange of the submaxillary 

 land of the dog, the cat, and the rabbit has been the subject of 

 numerous experiments. Tlie metabolism of these glands is increased 

 by stimulation of the chorda tympani. This increase is three or four 

 fold when the stimulation is accompanied by a flow of saliva ; when the 

 land is atropinised the increased metabolism is much smaller, and 

 amounts in many cases to about ."JO per cent, of the total metabolism. 



The Pancreas. — In the dog intravenous injection of secretion causes 

 a threefold increase in the metabolism of the pancreas, coupled with the 

 flow of pancreatic juice. 



The Intestines. — A study of the gaseous metabolism of the intestines 

 has furnished positive results. The metabolism is much increased during 

 absorption, whether of water or of peptone (tlog). 



The Kidney has been investigated in the dog and in the frog, the 

 former by the blood gas method, and the latter by perfusion with 

 Nager's solution. The following results have been obtained : Increase 

 in the flow of urine, induced by the injection of salts, causes a threefold 

 increase in the oxygen consumption of the dog's kidney, whether perfused 

 through the renal portal vein or through the renal artery. The meta- 

 bolism of the kidney is about twice as great when perfused through the 

 I'enal artery as it is when perfused through the renal portal vein. By 

 whichever path the perfusion fluid is led into the kidney, the metabolism 

 greatly increases when the organ is secreting ui'ine under the influence of 

 diuretics. 



There is no case of diuresis in either of the animals under observation 

 without greatly increased metabolism. 



Skeletal muscle was the only organ the gaseous exchange of which 

 had been seriously studied by previous workers. The Committee have 

 verified the coefficient of oxidation as determined by Chauveau and 

 Kaufmann. 



The production of lactic acid in muscle as the result of incomplete 

 oxidation has been investigated. The production of lactic acid under 

 anaerobic conditions varied with the time and was increased by heat, 

 stimulation, &c. 



III. Comparison of Results obtained from Different Organs. — .Some 

 results of general application have been gleaned from the study of the 

 metabolism of individual organs : — 



1. Increased vascularity does not of itself cause any change in the 



