Royal Society, London. 183 



Greville, in the chair. The business of the season opened, 

 as usual, with the Cronnian lecture, by Mr. Carlisle, on 

 the Poult mid particular Structure of theMiiscles of Fishes. 

 The excellence of Mr. Carlisle's former lecture on muscu- 

 lar motion awakened curiosity ; and if in the present he 

 has been less successful, it is perhaps rather owing to the 

 more limited nature of his subject, than to the want ot 

 ori2;inal observations and experiments. After several mi- 

 nure physiological explanations of the nature and peculiar 

 structure of the muscles of fishes, and their invariable 

 insertion in fleshy instead of tendinous matter, the au- 

 thor proceeded to detail his experiments on ihcir power 

 and particular use, in enabling the animal to move 

 with so much rapidity through a fluid so dense as wa- 

 ter. He ascertained that the miasclcs of the sides and 

 tail are solely those by means of which the fish ad- 

 vances ; that the pectoral and abdominal fins serve only 

 to raise or lower, and balance it in the water; and 

 ftiat, deprived of these muscles and again put into water, it, 

 remained at the bottom without being able to ascend, but 

 with the power of advancing as before. By cutting off the 

 pectoral and abdominal fins of one side, the fish lost the 

 power of balancing itself upright, fell on its side, and ad- 

 vanced slowly, tie accounted for what is vulgarly called 

 drowning in fishes, when caught by the angler's hook, 

 from the very great violence with which they at that time 

 strike the water, and consequent prostration of strength in 

 the muscles, that they fall on their side or back, and ap- 

 pear as if drowned. The effect would be the same if the 

 hook was placed in any other part of the body as well as 

 the mouth j exhaustion, and not L-ufi'o(?ation being the 

 cause. 



On the 14th, the reading of this interesting paper was 

 concluded. The fluids of fishes coagulate at about 160" of 

 Fahrenheit. 



On the same evening was read the Bakerian lecture on 

 the Force of Percussion, by Dr. Wollaston, secretary of the 

 society. Tlie nature of mathematical discussions render.^ 

 analysis extremely difficult, although Dr. Wollaston's lec- 

 ture possesses the rare merit of brevity and perspicuity. 

 The hitherto undefined, and perhaps undcfinable force ot 

 animal power has long exercised the ingenuity of mathe- 

 jnaticians, and Dr. Wollaston has wisely contented himself 

 with following Smeaton on that subject. His illustration 

 of ihe force of percussion, however, and of accelerated mo- 

 tion, he conceives to be somewhat novel, and to contain 

 M 4 something 



