Obfervations in Electricity. 397 
Smooth glafs rubbed with a rabbit’s fkin, dry and 
warm, acquires, I find, the negative electricity ; but if 
the fkin is cold, the glafs is excited pofitively. 
New white flannel has alfo fuch ftrong electric power, 
that fometimes I have excited fmooth glafs negatively 
with it. 
Confidering the ftrong eleCtric power of new white 
flannel, I thought that a piece of it rolled round the 
globe of an electrical machine would perhaps give a 
ftronger electricity on the prime conductor than the glafs 
itfelf. In order to try the truth of my fuppofition, I 
tied a large piece of flannel dry and warm round the 
globe of the machine; and for a rubber I applied the 
palm of my hand, then turned the winch, firft flowly, 
and afterwards brifkly; but, contrary to my expectation, 
I obferved that the electricity at the prime conductor, 
although pofitive, was fo weak, that the index of your 
electrometer was not moved. Surprifed at this event, I 
refolved to take off the apparatus; but I was more fur- 
prifed when, on removing the flannel from the globe, 
the former appeared fo ftrongly pofitive, that it darted 
feveral fparks to my arm and other contiguous bodies; 
and the latter remained fo ftrongly negative, that your 
electrometer upon the prime conductor inftantly elevated 
its index to about 45 0 . I repeated this experiment feve- 
