S70 Analysis of Scientific Books. 



5. An. Account of the Skeletons of the Dugong, two Horned Rhi- 

 noceros, and Tapir of Sumatra, sent to England by Sir Thomas 

 Stamford Raffles, Governor of Bencoolen. By Sir E. Home, 

 Bart.V.P.R.S. 



This memoir is illustrated by five plates, from drawings by 

 Mr. Clift, without reference to which the details would scarcely 

 be intelligible to the majority of our readers. Sir Everard 

 justly eulogizes the exertions of Sir Thomas Raffles in promot- 

 ing the pursuits of natural history and comparative anatomy ; 

 to his active interference we are indebted for the account of that 

 very singular animal, the Dugong, published in the preceding 

 volume of the Philosophical Transactions ; it is the only one yet 

 known that grazes at the bottom of the sea without legs ; be- 

 ing of the figure and form of a whale, the position and structure 

 of its mouth enables it to browse upon the fuci and submarine 

 algse like a cow in a meadow, and the whole structure of the 

 masticating and digestive organs shews it to be truly herbivo- 

 rous. It never visits land, or fresh water, but lives in shallow 

 inlets, where the water is two or three fathoms deep. Their 

 usual length is eight or nine feet. But a curious and, to some, 

 perhaps the most interesting part of the history of this animal 

 is, that the flesh resembles young beef, being very delicate and 

 juicy ; so that, as Sir Stamford, in the description of its dissec- 

 tion, remarks, '* it afforded no less interest under the knife, 

 than satisfaction on the table." 



6. On the Mean Density of the Earth. By Dr. Charles 



Hutton, F.R.S. 



We can never feel satisfied that it is fair to infer the density 

 of the globe from that of any protuberance upon its surface, 

 and are, therefore, not inclined to acquiesce in the importance 

 of Dr. Maskelyne's researches, who aimed at ascertaining the 

 mean density of the whole " terraqueous globe of our planet," 

 by measuring the dimensions of an insignificant mountain in 

 Scotland, and comparing its attraction on a plummet, with that 

 of the whole earth on the same. Mr. Cavendish sought the 

 solution of this problem by another method, consisting in as- 

 certaining the attraction on small pendulous balls, of two 

 inches diameter, by larger ones of ten inches diameter, as 

 compared with the attraction of the earth on the same. The 

 respective merits of these two experiments admit of considerable 

 discussion, and upon these it is not our intention to enter ; the 

 learned author of the paper before us is in favour of the for- 

 mer, and he bore an active share in the investigations con- 

 nected with it ; he took all the measurements upon which the 



