ix 



gruencies " ; " The Spherical Ellipse ref erred to Trilinear Coordinates " 

 " Cubics of the Third Class with Triple Foci, both Plane and Spheri- 

 cal " ; " Spherical Class Cubics with Double Foci and Double Cyclic 

 Arcs"; "On Sphere- Cyclides "; "On the Identity of the Nodes of 

 a Nodal Curve of the Fourth Order with those of its Quartic and 

 Sextic Contravariants " ; and "On the Genesis of Binodal Quartic 

 Curves from Conies." It appears to have been Mr. Jeffery's inten- 

 tion to prepare a text-book on his favourite subjects. Some pro- 

 gress was made in the preparation of such a work, and he was looking 

 forward with considerable interest to the publication of a treatise 

 which he hoped would prove useful to the student of the higher 

 mathematics. Only last summer, while the writer was enjoying his 

 hospitality, Mr. Jeffery exhibited to him a huge quantity of mathe- 

 matical manuscript, beautifully written out for the press, in the pre- 

 paration of which all his recent leisure hours had been devoted. He 

 was anticipating with evident enthusiasm the prospect of an early 

 completion of his labours in this branch of pure mathematics by the 

 production of a text-book; but, alas ! his wishes can never be real- 

 ised, for the small portion of the work prepared for the press exists 

 only as a fragmentary record of his mathematical talents, and of the 

 studious activity of his life to the end. His last original paper was 

 communicaced to the London Mathematical Society only a few weeks 

 before his fatal illness, and it was read at the meeting of the Society 

 on November 12, nine days after his decease. In addition to his 

 mathematical work, Mr. Jeffery has occasionally been occupied in 

 other fields of labour, mostly in classics, archaeology, and topo- 

 graphical history. In 1853 he wrote, as a coadjutor with Dr. E. 

 R. Humphreys, on classical composition in Greek iambics and Latin 

 prose. 



On his retirement from Cheltenham Grammar School Mr. Jeffery, 

 who was never married, took up his residence at Falmouth, partly 

 that he might be in a convenient locality to undertake the manage- 

 ment of a considerable amount of house property inherited from his 

 father, and partly on account of the comparatively mild winter 

 climate of his native county. Here he identified himself with the 

 active management of several local scientific institutions, especially 

 of the Royal Institution of Cornwall, at Truro, and the Royal Corn- 

 wall Polytechnic Society, at Falmouth, in both of which he had filled 

 the ofiice of Vice- President, and was a valued contributor to their 

 journals. His paper on the "Early Topography of Falmouth," in 

 the ' Journal of the Royal Institution of Cornwall,' is a most im- 

 portant contribution to the local history of that part of Cornwall. 

 Mr. Jeffery was the Honorary Secretary of the new Falmouth Ob- 

 servatory, in which he has taken a great interest since its foundation. 

 Mr.^Kitto, the Superintendent, has remarked that he was much 



d 



