INDEX. 
S 
pagi 
Saltpetre^ observations respecting the natural production of 
it on the walls of subterraneous and other buildings, 
its spontaneous formation more extensive and rapid 
in winter than in summer, - - _ 
■ a frosty, clear, and dry state of the atmosphere par- 
ticularly favourable to its natural production, 
— ' — experiments to ascertain tiovv far the free presence 
of atmospherical air is necessary in the natural formation 
of it, - 
Salts, on the nature of those termed triple prussiates, and on 
acids formed by the union of certain bodies with the ele- 
ments of the prussic acid, - . _ 
Seppings, Robert, Esq. On a new principle of construct- 
ing His Majesty’s ships of war, 
Ship, forces acting on it, - 
longitudinal pressure acting on it. 
Ships, remarks on the employment of oblique riders, and on 
otlier alterations in the construction of them, 
the cause of their breakimr ti ansverselv, - • 
lateral curvature of them, 
2;roundinii of them, ... - 
causes which promote the decay of their timbeis, 
—-comparative advantages ofdilferent angular positions 
of their timbers, . . - - 
Ships of war, on a new principle of constructing them, 
Stars, of those in remai kable situations with regard to nebula?, 
of two with nebulosity between them, 
of those vvitii nebulosities of various shapes attached 
to them, _ . - _ - 
of those with nebulous branches, 
— - nebulous . _ - _ 
of those connected with extensive windings of nebulosity, 
of small patches consisting of them, mixed with nebu- 
losity, - * - - - 
of the aggregation of them, 
— - of irregular clusters of them, 
of clusters of them, variously extended and compressed, 
of clusters of them of a peculiar description, 
— - of differently compressed clusters of them, 
— - of the gradual concentration and insulation of clusters 
of them, . . - - - 
508 
514 
517 
518 
527 
285 
304 
307 
303 
313 
314 
314 
3)5 
313 
285 
249 
250 
251 
253 
254 
256 
257 
265 
266 
26S 
269 
271 
070 
^ f ^ 
