1 3b Memoir on the Temperature of 



those advanced by sound philosophy, will in future be etl- 

 tiicly proscribed ; and M. Peron subMitntcs in its stead this 

 consequence of the experiments which he made on this 

 subject. 



The relative temperature of the water of the sea increases 

 during its agitation, but its absolute temperature always de- 

 creases. 



The second section of IM. Pcron's memon- contains aii 

 account of experiments which may be made at great depths. 

 The author here establishes a great distinction between ex- 

 periments of this kind made along the coasts, and tliose re- 

 peated in the opvn sea at a great distance from the conti- 

 nents and h\rgc ibi.mds. From his examination of experi- 

 ments of the (irst kind, those made along the coasts by 

 Saussure and JMarsigh in the Mediterranean ; by Donati in 

 the Adriatic ; and by himself in the sea which washes the 

 western coast of New Holland, it results that, cceteris pa- 

 %ilus, the temperature of the sea along the coasts is greater 

 •at equal depths than in the middle of the ocean 3 that it 

 seems to Increase as one approaches the shores ; and that 

 these writers themselves furnish objections against the uni- 

 ibrm temperature of 10°, which has hitherto been admitted 

 as the mean temperature of the interior part of the globe 

 either in its solid or li(juid part. 



For the above experiments, and those about to be men- 

 tioned, M. Peron employed an apparatus, invented by him- 

 self, which appears indeed to be superior to all those hi* 

 therto emplovfd for the same purpose. By arranging suc- 

 cessively around his thermometer a stratum of air, glass, 

 charcoal, wood, tallow, and resin, he was able to unite 

 under a very small volume all those bodies which are the 

 worst conductors of caloric, and in such an order, that this 

 property of being a bad eonducU)r necessarily became still 

 less ; M. Peron having set out from tills principle, that 

 caloric., as well as electricity, can with the greater difficulty 

 penetrate a stratum of a given thickness, as the bodies 

 which compose it are more different in their nature. This 

 part of the author's labour has been universally approved. 



The author then proceeds to the temperature of the sea 

 at gi'cat depths : — '* We have now arrived," says he, " at 

 the third and ninth part ol' the experiments which might be 

 attempted on the heat of the sea water. It Is also the most 

 delicate and the most interesting, in consequence of the va- 

 luable data it may furnish us in regard to the internal phy- 

 sical state of the globe at depths which cannot be reached 

 in the solid part." He then gives the result of the experi- 



meots 



