On the developement of Magnetism by Rotation. 287 



lived. Many of them at the approach of death betake them- 

 selves to hidden retreats, as if to withdraw themselves from 

 the rapacity of the carnivorous ones. Such, for instance, are 

 the deer, of which nearly entire skeletons are found, although 

 the parts be disseminated ; such also are the great carnivorous 

 animals, as the lion, the bear, the hyena, which seize their prey 

 in the dark, and carry them away to devour them in the cavi- 

 ties which serve them for dens. Everything in the Gautier 

 cave attests the prolonged stay of these large Carnivorae. 

 Among the heaps of bones of every kind, some show the marks 

 of sharp teeth which have bruised and ground them ; others 

 appear only indented, their harder consistence having protect- 

 ed them. Another proof of much weight is the great quan- 

 tity of fossil excrement of hyenas, and which would not have 

 been collected in such abundance, in a situation where the re- 

 mains of some ten hyenas may be found, if these hyenas had 

 not dwelt there. I conclude from these summary observations, 



Imo, That this cave has been a den of carnivorous animals. 



2do, That the cavern has been traversed by a stream of 

 water, which has deposited mud on the bone^ which it found 

 on its passage. 



LuNEL, 9>0th January 1827. 



Art. ^\ .-^Observations on the History of the Developement of 

 Magnetism by Rotation. By S. H. Christie, Esq. M. A. 

 F. R. S. &c. In a Letter to the Editor. 



Dear Sir, 



Had the tenor of Mr Barlow's letter in your last Number 

 been in accordance with its professed object, the terminating 

 of the correspondence, that object would have been attained. 

 But since, instead of leaving " whatever may be in dispute to 

 be judged of from what has been already stated," Mr Barlow 

 has given loose statements of particular circumstances, the 

 real object appears to be very different ; and I cannot avoid 

 making some remarks, which, however, shall be as few and as 

 concise as possible. 



The origin of the correspondence, which I regret has oc- 

 cupied so many pages of your valuable Journal, was, that in 



