CHAP. XII.] CORRESPONDENCE. 381 



The desideratum is to set a Don and a Freshman to 

 observe and register (say) the vibrations of a magnet 

 together, or the Don to turn a winch, and the Freshman to 

 observe and govern him. 



FROM PROFESSOR TYNDALL. 



Monday. 



MY DEAR MAXWELL Why ... did you run away so 

 rapidly. I wished to shake your hand before parting. 

 Yours ever, JOHN TYNDALL. 



To MRS. MAXWELL. 



20th March 1871. 



There are two parties about the professorship. One 

 wants popular lectures, and the other cares more for experi- 

 mental work. I think there should be a gradation popular 

 lectures and rough experiments for the masses ; real experi- 

 ments for real students ; and laborious experiments for first- 

 rate men like Trotter and Stuart and Strutt. 



FROM C. J. MONRO, Esq. 



Hadley, 21st March 1871. 



... I never observed before that ancient colour- 

 nomenclature was more discriminate than ours for the 

 more " violently " refracted tints as compared with the 

 less ; but I think there must be something in it. But 

 I have always suspected that they referred colour to a 

 positively distinct set of co-ordinates from ours. Gladstone 

 says something of this sort in Homer ; who put it into his 

 head I can't think ; if he made it out for himself I should 

 be very sorry to agree with a man who does not believe in 

 spectrum analysis, and does believe that Leto is the Virgin 

 Mary. Such queer applications of words of colour one does 

 find. You know the " pale " horse of the Apocalypse (vi. 8) ; 

 well, that is ^Xo>/>o5, which is usually " green," you know. 

 General Daumas says the Arabs call " vert " what the 

 French call " louvet " in horses ; and louvet, in Littre, " Se 

 dit, chez le cheval, d'une robe caracte'risee par la presence de 



