TRANSACTIONS OF THE SECTIONS. 109 



empyreumatic oil, carbonic acid gas, carbonic oxide, oxygen, nitrogen, 

 aqueous vapour. 



From a number of experiments on the elimination of carbonic acid 

 during respiration, he arrived at the following results : — that 266'66 

 cubic feet of atmospheric air pass through the lungs of an adult in 

 twenty-four hours, of which 1 0*666 are converted into carbonic acid, 

 yielding 5*45 ounces of carbon, or 1^4^-628 pounds annually. The 

 average amount of carbonic acid found in atmospheric air in which 

 animals had expired was found to be, for warm-blooded animals, 

 12*75' per cent., for the cold-blooded animals, 13'116 per cent. When 

 the animals were removed, on becoming comatose, the average amount 

 of carbonic acid was found to be 10"42 per cent. On confining a 

 taper until its extinction, the quantity of carbonic acid found was 

 S'O^e per cent. From hence it would appear, that an atmosphere 

 which has ceased to support combustion can support animal life for 

 some time. 



Report of Ten Cases of Calculus treated hy Lithotrity. 

 By Dr. CosTELLo. 



The patients were of ages between fifty-three and seventy-six, the 

 stones varying in size from that of a pigeon's egg to that of a hen's 

 egg. The lithotrite was successively applied at sittings of from thirty 

 to fifty seconds. Dr. Costello strongly insisted on the necessity of this 

 point, especially at the commencement of the treatment, as the consti- 

 tution is thus saved from the shock and re-action which follow pro- 

 tracted operation. In one of the cases the collected fragments of the 

 removed calculus filled a bottle capable of containing at least four 

 fluid ounces. The patient had suffered upwards of ten years ; during 

 the treatment he superintended the farming of his estate as usual, 

 without any inconvenience ; the entire of the ten cases were cured. 



On the Cellular Structure of the Ivory , Enamel, and Pulp of the Teeth, 

 as well as of the Epithelium, and on some other interesting points of 

 Odontology, By A. Nasmyth, M.R.C.S., F.L.S., F.G.S., Sfc. 



On Instruments made from Softened Ivory. By Dr. Ludwig Guter- 



BOCK. 



Instruments made of softened ivory were presented to the Section, 

 and described by the author. The ivory, being fashioned to the re- 

 quired figure, is softened by dilute muriatic acid, which removes the 

 hardening earth. In a brief memoir. Dr. Giiterbock showed that the 

 first idea of the preparation was not due either to the German or 



