49^ PHILOSOPHICAL TRANSACTIONS. [aNNO 1720. 



I repeated this experiment without the feather, viz. by a single thread of silk 

 only, of about 5 or 6 inches long, which was made to stand extended upright as 

 abovementioned, without touching the paper ; then placing my finger near the 

 end, it would avoid, or was repelled by it ; but on placing my finger at about 

 the same distance from a part of the thread, that was about 2 inches from the 

 end, it was then attracted by it. 



The several bodies here found to be electrical, are, 1 . Feathers. 2. Hair. 

 3. Silk. 4. Linen. 5. Woollen, 6. Paper. /.Leather. S.Wood. 9. Parchment. 

 10. Ox-guts, in which leaf-gold is beaten. 



A Letter to Dr. Halleyy R. S. S. in answer to some Objections made to the 

 History of the Antiquity of the V^en£real Disease, By Mr. Beckett, Surgeon, 

 F.R.S. N°366, p. 108. 



I find there have been two objections made against what I have advanced on 

 the antiquity of the venereal disease. The first is, that the venereal disease so 

 well known among us now, and the leprosy of former ages, could not be the 

 same disease, because the leprosy is not to be conquered by salivation, which 

 the other generally very readily yields to. In answer to this, I am to observe, 

 that the leprosy, which we have among us at this time, affects only the surface 

 of the body, the skin generally appears scaly, with a certain deep red colour, 

 or small sores upon removing the scales, and sometimes a scabbiness, with a 

 redness of the skin, which affects different parts of the body. I have known 

 both the cheeks only afl^ected, both the arms for the breadth of the palm of 

 the hand, sometimes the breast, the legs, and other parts. But this may con- 

 tinue on the patient during his life, as it frequently does, and never make any 

 further progress ; which shows it to be a cuticular disease. In these cases, on 

 salivating, the scales generally fall off, the redness disappears, and the cure will 

 seem to be completed : but in a month or two, the same inconveniences gene- 

 rally attend them as before. But we ought not to conclude, that because our 

 leprosy will but rarely be cured by salivation, and the pox generally will, that 

 many of those persons the ancients judged to be leprous, were not really vene- 

 real : for their leprosy, as they called it, was a quite different disease from ours. 

 Had there been any proof brought that persons had been salivated in their 

 leprosy, and failed of cure, it would have determined the case: but on the 

 contrary, we are assured by the learned Dr. Pitcairn, in his Dissertation on the 

 Ingress of the Lues Venerea, that the leprosy, before the Neapolitan disease 

 was talked of, was cured by mercury, and now since it changed its name, it is 

 no longer heard of. Thus we find that their leprosy and our venereal disease 



