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STATE BOARD OF AGRICULTURE. 



by means of potassium hydroxide, the oxygen was absorbed by means of alkaline 

 pyrogallate and what remained was considered as residual gas. In the case of previous 

 experimenters, the residual gas has been called nitrogen, to me a very presumptuous 

 proceeding, inasmuch as there is apparently much concealed in the residual gas con- 

 cerning which we know little. In the lower curves of the pipette a little mercury was 

 placed to act as valves to prevent diffusion. The three way stop-cock of White's burette 

 enabled us to fill the connecting tubes between the pipette and burette completely. By 

 this means all errors were reduced to a minimum. 



The milk used in these experiments came from one cow, and usually from a single 

 quarter. In none of these analyses did the milk come from more than a single quarter, 

 since a quarter contained sufficient milk to fill the container and the possibility of air 

 entering in changing from one quarter to another was thus avoided. It was found in 

 several cases, too, in our work that should the milk become exhausted in a single quarter 

 the tissues closed over the apertures of the milking-tube and prevented the further 

 flow of the mercury; this further demonstrates that no air could possibly enter by 

 means of the apertures in the milking-tube. The whole apparatus including tubes, 

 container, connections, and pipette was severely tested by several preliminary trials 

 from the starting of the milk from the udder through to the securing of the gas from 

 the milk by pumping. Everything had been verified by these preliminary trials. (In 

 all of our gas analyses the barometric pressure has been reduced to 760 mm. at 0° C, 

 unless otherwise stated.) (A uniform pressure during pumping was maintained by a 

 large galvanized iron tank filled with water in which the entire apparatus was placed.) 



IV. ANALYSES OF THE GAS-COXTEXT OF MILK BEFORE EXPOSURE TO AIR. 



The following six samples were run through and the gases analyzed with these 

 results: — 



TABLE I. 



The above six analyses furnish an average which is lower than that of Pfliiger. but 

 this does not appear to detract from the value of the work of either after considering 

 the possible variation occurring in the gas-content of milk from the same quarter of the 

 cow. The amount of carbon dioxide obtained in the above analyses is in percentages. 



80.58. 78.35, 81.73, 81.97, 80.1G and 86.19. 



The averages of these percentages is 81.49% per cent. 



Pfliiger obtained in his anaylses 90.45 per cent and 87.16 per cent. 



The average of Pfltiger's analyses therefore would be 88.S0 per cent. 



