126 



JAMES CLERK MAXWELL. 



[CHAP. v. 



pictures of the statue of Ariadne and the beast seen from 

 two stations, which, when viewed properly, appeared very 

 solid. 



Since then I have been doing practical props on com- 

 pression, and writing out the same that there may be no 

 mistake. The nicest cases are those of spheres and cylinders. 

 I have got an expression for the hardness of a cricket ball 

 made of case and stuffing. I have 

 also the equations for a spherical 

 cavity in an infinite solid, and this 

 prop : Given that the polarised 

 colour of any part of a cylinder 

 of unannealed glass is equal to the 

 square of the distance from the 

 centre (as determined by observa- 

 tion), to find 1st, the state of 

 strain at each point ; 2d, the tem- 

 perature of each. 



I have got an observation of 

 the latitude just now with a saucer 

 of treacle, but it is very windy. 



Pray excuse this wickedly 

 perplexed letter as an effect of 

 the paucity of our communica- 

 tions. If you would sharpen me 

 a little it would be acceptable, but 

 when there is nobody to speak to 

 one [loses] the gift of speech. . . . 



This is the likeness of a SKEW SCREW 



SUBFACE. 



To THE SAME. 



31 Heriot Row, Edinburgh, N.B., 

 Monday, Nov. 5, 1849. 



I go to Gregory to Chemistry at 1 0, Morale Phil, at 1 2, 

 and Pract. Chem. at 13, finishing at 14, unless perhaps I 

 take an hour at Practical Mechanics at the School of Arts. 

 I do not go to Sir W. H. logic, seeing I was there before. 



