1888.J On the Plasticity of Glacier and other Ice. 



361 



Examining the bar at the end of the experiment, we counted about 

 thirty columns in a section, most of which ran the full length of the 

 bar. The largest had a sectional area of about 35 sq. mm. 



Experiment No. 10. Rough Apparatus. — The specimen was a bar of 

 lake ice, with the crystalline columns running obliquely across at an 

 angle of 45° to the length of the bar. The area of section was 

 5*5 sq. cm. The indicators, &c, were arranged as before. The tem- 

 perature at the time of observation, and the minimum temperature 

 were observed ; the maximum and mean temperatures are estimated. 

 The fourth and fifth columns give the actual extension during each 

 interval. They are probably correct to 0"02 mm., as the multiplica- 

 tion was 35. 



The rate shows a decided tendency to decrease, only slightly 

 checked by the rise of temperature. The glass needles were put at 

 right angles to the columns as well as to the length of the bar. 



