546 



Mr. T. Andrews. 



[June 10, 



temperature of the ice cylinder from exterior to centre until it reached 

 an uniform temperature of 32° F. was simultaneously periodically 

 taken by the thermometers Nos. 1, 2, 3, and 4, and the results are 

 graphically recorded in Table No. 1. The surface of the ice was kept 

 covered to a depth of some inches with sawdust. 73J hours were re- 

 quired for the mass to attain the temperature of 32° F. from 

 zero (0° F.). 



Table I. — Relative Conductivity of Ice and Snow compared by the 

 time required under equal conditions in each case for the respec- 

 tive mass of Ice or Snow to acquire an uniform temperature 

 throughout. 



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z 













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1 



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i 



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 — 



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 r 











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XX.ll 



i I til ll 1 11 ! - LLLU 



3 375 6-75 10-125 



Distance iv inches frrm art -n -mfrrr-nn tr etnlr 

 \aagpuircng rr.sptcfr'wO/ the temjx ra-lmt* cf 32" /• * 



Temperature of ice and snow cylinders at commencement = Zero (0°) F. 

 Temperature surrounding ditto = 32° F. 



The relative conductivity of snow was taken in a similar manner. 

 An equal volume of fresh fallen snow was placed in the iron tank, A, 

 and only very lightly pressed to ensure solidity of the snow, but so as 

 to avoid regelaiion. Its weight was 1 cwt. 2 qrs. 14 lbs. The iron 

 tank was then surrounded by the freezing mixture until the internal 



