xi.] FAILURE OF HEALTH. 383 



I think, printed in January 1851, I attributed the softness 

 of ice to the fact, then recently stated, that water 

 gives out its latent heat during congelation down to a 

 temperature sensibly below 32. Connecting this state- 

 ment with certain experiments I have lately made, I 

 am in a condition to show that a film of water ready to 

 be converted into ice viscid water or soft ice between 



suri-u-es of ice in a thawing state must solidify. I 

 shall send you by and by a short paper on the subject. 

 If I am correct, the cementation or "regelation" of 

 thawing surfaces of ice is merely another phraseology for 

 the assertion that ice softens, or it absorbs latent heat 

 gradually, about ^2, where all substances do, such as 

 :, spermaceti, &c., which soften by degrees. Of course 

 the fracture may be molecular as well as finite, and then 



lermed properly plasticity. 



' I am truly glad to know that your visit to us was not 

 altogether a failure, notwithstanding our disappointment 

 about Balmat. My inactive state makes me a bad 

 entertainer, and it is only after years of discipline that I 

 can bring myself to acquiesce in a mode of life, which as 

 you may fancy is strangely at variance with my whole 

 previous habits down to the age of 42.' 



The summer was spent at Pitlochrie, varied only by a 

 visit to Fettercairn and an expedition to Loch Rannoch. 

 From his highland cottage he writes to Dr. Symonds. 



To DR. SYMONDS. 



' EDINBURGH, May 30/A, 1858. 



1 . . . You must not forget that we too have a very 

 respCM tal)lc Sleepy Hollow at Pitlochrie, where our 

 lir en the grass and read poetry and listen to 

 Muirnwrs of the Tuinmel. Seriously, we will take no 

 n fusal about coming to Dysart Cottage this sumin.-r. 

 season is open to you to choose. All t i \ 

 nldle of Jiii i like to us/ 



During tln> s ;umer Dr. AYln'\\vll and Lidy 



Affleck, whom he had lately married, \ tlie 



