336 Mr. nairne's Account of the 
tenth, viz. its whole length being now barely eight 
inches and nine tenths inftead of ten inches that it was 
at firft. I then weighed it in a pair of fcales that would 
turn with lefs than the eighth part of a grain ; but could 
not perceive, that there was any fenlibie difference in 
the weight. I tried it with a pair of callipers, and it 
feemed to be rather thicker. 
I intended to have patTed feveral more difcharges of 
the battery through the wire, but the fixteenth melted 
it. 
I have likewife fhewn this extraordinary effecSl of elec- 
tricity to Dr. Priestley, Mr. Magellan, and feveral 
other gentlemen, in whofe prefence I paffed fix dif- 
charges of the fame battery through a piece of the fame 
wire, exactly ten inches in length ; and on meafuring it, 
it was found to be fhortened four tenths and a half of an 
inch, which is juft three quarters of a tenth for each dif- 
charge. Dr. priestley then took a piece of the fame 
wire, of exactly the fame length, and heated it red-hot 
in the common culinary fire. This wire being after- 
wards meafured was found to continue of its original 
length of ten inches, not being in the leaft fhortened. 
I have generally found, that if the iron wire was firft 
annealed in the culinary fire, the fame ftrength of charge 
melted it. 
I have 
