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fent me the following queflions, which he thinks 
tend to throw further light upon this fubjeC, and 
has defired my opinion upon them. As thefe may 
poflibly hereafter be of public utility, 1 have taken 
the liberty of communicating them to your Lordfhip. 
I. What fort of apparatus is ufed at Philadelphia? 
II. Whether there is not fome improvement to be 
made to their methods? 
III. In what manner this apparatus may be adapt- 
ed to powder magazines ? 
IV. Into what place the thunder may be conduc- 
ed, where there is no river near, to anlwer the pur- 
pole of the fea about fhips ? 
V. Whether the apparatus might not eleCrify the 
air, fo as to occalion lightning, which was, he be- 
lieves, the caufe of the death of Profeffor Richmann 
of Peterfburg ? This apparatus may not be danger- 
ous to dwelling houfes, where the fire may flip with- 
out any manner of ride ; but may be attended with 
the mod; dreadful confequences to a powder maga- 
zine, where the fmalieft lpark may occalion the ex- 
plofion of the whole. 
VI. Whether the fquare, or the circular form of 
building, will be eafieft adapted to the apparatus ? 
VII. Whether an iron bar fixed on the top of the 
building, to fupport a weather-cock, may not at- 
tract the thunder bolt, and be ccnfequently dangerous 
to all buildings; but more efpecially to powder ma- 
gazines ? 
VIII. Whether there is not fome particular man- 
ner of buildings, invented of late, adapted to pow- 
der magazines ; either to diminifh the fiiock of the 
explofion, or to fecure them againd any accident, by 
the method ufed at Philadelphia ? 
Mr. 
