688 PHILOSOPHICAL TKANSACTIONS. [aNN£> 1780. 



into the narrow part of this substance, we could pass a probe very readily both 

 upwards and downwards, so as to be convinced, it was really hollow all the way. 

 On introducing a blow-pipe, the upper part was expanded into a large cul de sac 

 and the lower distended pretty much like a large vessel. The appearance of this 

 man during his illness, as well as at the time of his death, was exactly similar 

 to what Mr. C. had frequently observed in patients who had lingered under, and 

 been destroyed by, slow inflammations of the viscera. His complaints in the 

 abdomen only indicated a diseased bladder, and for that reason Mr. C. opened 

 him: for he was not even so much emaciated as patients under that disease 

 often arc. 



JiX. On the Effect (if Electricity in S/wrieiiing JVires. By Mr. Edward 



Nairne, F. R. S. p. 334. 



Exper. Mr. N. took a piece of hard-drawn iron wire, 10 inches long, and -pi- 

 of an inch in diameter. This wire was held in a perpendicular position between 

 two brass pincers, the upper one being connected with a glass pillar, that the 

 whole charge of an electrical battery might pass only through the wire fastened 

 between them. These upper pincers were moveable, for the sake of slackening 

 the wire occasionally; and in the experiment they were fixed with a screw, so 

 that the wire hung somewhat loose between them and the lower ones. He then 

 charged a battery, containing 26 feet of coated surface, till the index of the 

 electrometer was raised to 50°: it was then discharged through the wire, and 

 immediately after the wire was seen to shorten by its drawing nearer to a straight 

 line between the fixed pincers. If the wire was put so loose that the moving of 

 the upper pincers -^\ of an inch would draw it just straight, one discharge of 

 the battery through it would then draw it to a straight line. Mr. N. discharged 

 the same battery 9 times through a piece of the same wire, which was also of 

 the same length, which was slackened each time before the discharge went 

 through it. After the 6th and Qth time the wire was measured, and found to 

 have shortened in the proportion of -^^- of an inch each time. 



Mr. N. afterwards discharged the battery 6 times more through the same 

 piece of wire, which made 15 times in the whole, and found it had continued 

 shortening nearly in the same proportion, the wire having been shortened by the 

 15 strokes full one inch and -^, viz. its whole length being now barely 8-jV 

 inches, instead of JO inches that it was at first. He then weighed it in a pair 

 of scales that would turn vvitli less than the 8th part of a grain; but could not 

 perceive, that there was any sensible difference in the weight. He tried it with 

 a pair of callipers, and it seemed to be rather thicker. He intended to have 

 passed several more discharges of the battery through the wire, but the l6th 

 melted it. 



