in EleSir icily. 669 
that I took, fparks between one and two feet long from 
the front, furface of the firft disk by approaching my 
knuckle to it. I then applied a tin conductor to it, about 
fix feet long and fix inches diameter, divided into two 
branches, the extremities of which were furnilhed 
with a thick filver lace fringe inftead of points. The 
fparks from this conductor were about four or five inches 
long, appeared to be very thick, were very brilliant, and 
fo ftrong, that I did not chufe to receive many of them; 
nor did thofe who came to fee the machine care to receive 
more than one. As thefe fparks fucceeded one another 
at fliort intervals, I think they would have been much 
longer if every thing had been adapted for that purpofe ; 
as I faw afterwards done at Mr. nairne’s, who contrived 
to obtain fparks of twenty inches long and upwards from 
a large glafs cylinder. 
Iconfidered this pafte-board machine rather as a rough 
sketch of an apparatus, by which I conceived the hope of 
obtaining an electrical power of almoft any degree re- 
quired, than as a compleat machine. My intention was 
to find out a contrivance by which a very great quantity 
of eleCtrical fire might be collected without great ex- 
pence and without much danger of breaking the appa- 
ratus, w’hich two articles cannot be avoided when you 
make ufe of uncommon fize glafs cylinders or disks. 
Vol. LXIX. 4 S I faw, 
