74 JAMES CLERK MAXWELL. [CHAP. IV. 



attention amongst scientific men. Such ideas had a 

 natural fascination for Clerk Maxwell, and he often 

 discoursed on " egg -and -dart," "Greek pattern," 

 " ogive," and what not, and on the forms of Etruscan 

 urns. One of the problems in this department of 

 applied science was how to draw a perfect oval ; and 

 14. Maxwell, who had by this time begun the (purely 

 geometrical) study of Conic sections, became eager to 

 find a true practical solution of this. How completely 

 his father entered into his pursuit may best be shown 

 by the following extracts from Mr. Clerk Maxwell's 

 Diary : 



1846, 

 February. 



W. 25. Called on . . Mr. D. E. Hay at his house, Jordan 

 Lane, and saw his diagrams and showed James's Ovals Mr. 

 Hay's are drawn with a loop on 3 pins, consequently formed 

 of portions of ellipses. 



Th. 26. Call on Prof. Forbes at the College, and see 

 about Jas. Ovals and 3 -foci figures and plurality of foci. 

 New to Prof. Forbes, and settle to give him the theory in 

 writing to consider. 1 



March. 



M. 2. Wrote account of James's ovals for Prof. Forbes. 

 Evening. Eoyal Society with James, and gave the above 

 to Mr. Forbes. 



W. 4. Went to the College at 1 2 and saw Prof. Forbes, 

 about Jas. ovals. Prof. Forbes much pleased with them, 

 investigating in books to see what has been done or known 



1 Part of the entry on the same day is : " Parliament House. 

 Return with John Cay, called at Bryson's and suggested to Alexander 

 Bryson my plan for pure iron by electro-precipitation from sulphate or 

 other salt." It is interesting to observe this revival of his youthful 

 ardour for science in the old companionship, following upon his sym- 

 pathy with the efforts of his son. 



