110 Correspondence of J. Nicklés. 
Possibly it is to this cause that we must refer the explosion so often no 
ticed in the manufacture of potassium and sodium, the cause of which 
great Greenwich circle 
expense of the British 
Mr. Piazzi i ‘i omical ins ruments. The new 
gnetic and me 
Paris under the direction of Mr. Welch. The Bureau of Ordnance 
exhibit the great theodolite which it has ernployed in triangulation, ané 
examples of charts on different scales. The department of geological 
charts has also prepared a collection which will give a complete idea of — 
its labors. The men of science in England at first felt some repugnance — 
bine, James, Willis, Lord Rosse, Wrottesly, Snow Harris, Wheat 
Lassell, Grove, Warren de la Rue, Arnott, Gassiot, Brodie, and Frank- | 
land. Many of the great institutions figure also in the list, viz., Univer § 
spital for the 
