Experiments on the TrttnfmiJJion of Sound. 413 



force than folid bodies, and modified it in a remarkable manner. The tone in each of the 

 firings appeared to be different, and the intenfity followed this order : — gut, hair, filk, hemp, 

 flax, wool, cotton. 



From the foregoing experiments it follows: — !. That hard bodies and ftretched ftriiigs 

 tranfmit found much better than atmofpheric air. 2. That each of tliefe mediums tranfniits 

 it in a manner which is peculiar to itfelf, fo that the kind and intenfity of the found are 

 never exaftly the fame, as far as can be judged on trials which do not always prefent very 

 ftriking refults *. 3. That in general wood tranfmits found very well ; that the metals 

 tranfmit it with fomewhat lefs energy, and that ftretched firings occupy the third place in 

 the fcale of power in this refpeft. 



Experiment V. Being determined to extend my refearches, I caufed the found of the watch 

 to'pafs through pieces of zinc, antimony, glafs, fal gem, gypfum, dried clay, and marble. 

 As I could not give the fame form to thefe different fubdanccs, I was unable to determine 

 with precifion their refpeflive powers of tranfmiffion ; but I obferved that all thefe bodies 

 tranfmitted founds better than air, and thnt it was modified in a particular manner by each 

 of them. Marble was remarkable for the little force with which it tranfmitted the fonorous 

 movements. Two pieces of this fubftance, of different form and fize, propagated it in a 

 weak and-almofl infenfible manner. 



Thefe are the experiments I have made with folid bodies. To complete the feries, it re- 

 mained to fubmit fluids to fimilar trials. 



1 have already publithed my experiments on aeriform fubftances f . In this place I fhaU 

 relate thofc I have made upon hquids. This part of my operations required a different 

 procefs. 



Experiment VI. I clofed all the joints of my watch with foft wax, and then fufpended it 

 by a fdk thread. In this ftate I hung it by an iron branch fixed in the wall, fo that the 

 watch remained fufpended in the middle of a glafs velTel five inches in diameter, and feven 

 inches high, taking care that neither the watch nor the thread touched the veHel in any part. 

 I remarked the kind of found afforded by the watch, and the diflance at which I eeafed to 

 hear it. After having marked this point, I then filled the vefTel with water, into which 

 1 again fufl'ercd the watch to defcend, with the fame precaution of not fulferlng it or the 

 thread to touch the velTcI. 



The tone (timbre) was changed in the water in a ftriking manner. The found was pro- 

 pagated in fo lively a manner that the glafs, and a fmall table of wood, on which it Rood at 

 a diflance from the wall, feemed to undergo dired percuffions from a folid body. But what 

 appeared aill more allonifliing was, that in the mida of all thefe agitations the fluid in 

 which the watch was plunged was perfeflly tranquil, and its furface not in the llightell de- 

 gree aglnted. 



By fubftituting different liquids in the- place of the water, I had refults in general ana- 

 logous to thofe I had obtained with that fluid ; but each medium gave a different modifi-. 

 oation to the found, of which the intenfity was noted as follows : 



'■• Such chie/ly ate thofe which were obtained with the cylinders of wood, and llretclicd ftrings. P. 

 + Mem. de f'Acad. Roy. dcs Sc, de Turin, '■^f,^,, 1737. 



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