430 



Natural History in Foreign Countries, 



prevalent. A reprint of the third edition of Mr. Bakewell's Introduction to 

 Geology^ under the superintendence of Professor Silliman of Yale College, 

 has just issued from the press of Messrs. Howe of Newhaven, the execution 

 of which is very creditable to the American book trade. The Professor 

 states, in his preface, that he believes he is rendering a service to his 

 country, by encouraging the republication of this valuable work, con- 

 spicuous for its perspicuity and attractiveness : " but my immediate motive," 

 he says, " for recommending this republication was, that I might place in 

 the hands of my own classes a comprehensive treatise on geology, which 

 they would be willing to read, and able to understand." —r N. D, Decem- 

 ber 15. 1829. 



SOUTH AMERICA. 



106 



Sir, I embrace this opportunity of sending you a few remarks which 

 I have made on the voyage as far as this place ; if they are worth a place 

 in your Magazine, I shall be obliged by your noticing them. I am sorry to 

 say that our stay at Rio is only for a few days, to replenish our water, 

 otherwise I should have been able to give you an account of the museum 

 and botanic garden. The above {fig. 106.) is a diagram of my journal of the 

 heat of the atmosphere since we left London. The height of the thermo- 

 meter was taken regularly every day, between the hours of twelve and one 

 at noon ; the difference of latitude 3'ou will see at the bottom for every 

 seven days. We had but very little rain, and that between the seventh and 

 third degrees of north latitude. I have also remarked, that the thermometer 

 seldom fell more than three or four degrees below the meridian heat be- 

 tween the tropics. When in lat. 9 N. and long. 22 W., the 7th October, 

 we were visited by a couple of swallows (jFZ^irundo rustica) ; they appeared 

 tired, and settled several times on various parts of the rigging ; on the 8th 

 they were joined by two more. In the course of the day some cheeses had 



