370 Analyses of Boohs. [Nov. 



Such are the arguments brought forward by our author to show 

 that valleys were not excavated by rivers. Some of them possess 

 force ; but others, the last two, for example, seem to me to be 

 of little weight. Perhaps, therefore, it would have been better 

 to have omitted them. Our author has not paid much attention 

 to the rhetorical, or even the logical method cf arrangement, nor 

 to a maxim of which reasoning authors should never lose sight, 

 that whatever does not strengthen their reasoning in reality 

 weakens it. * 



Buffon ascribed the excavation of valleys to the ordinary 

 action of the sea at a time when it covered the present surface 

 of the earth. But our author is of opinion that this cause is ina- 

 dequate, and that they must have been excavated by a debacle, 

 or deluge, which must have been universal, or at least exceeded 

 the height of the highest mountain. 



Pallas ascribed this debacle to the tremendous volcanic erup- 

 tions, which, in his opinion, occasioned the Moluccas, Philip- 

 pines, Sec. to emerge from the sea. His reason for adopting this 

 notion was, that he thought that it afforded an explanation of 

 the existence of the bones of tropical animals in Siberia. But 

 our author thinks the explanation insufficient, for the following 

 reasons : 



1. Had the carcasses of tropical animals been wafted by a 

 debacle, moving with violence sufficient to excavate valleys, and 

 waft along huge bowlderstones, they must have been abraded 

 and dashed to pieces before they reached the polar regions of 

 Siberia ; yet they have been found entire, and even covered with 

 the skin and hair. 



2. Were we to suppose them to have moved only at the rate 

 of 100 miles a day, they must have been putrid long before they 

 reached their destination, which our author estimates at 36,000 

 miles. I am at a loss to conceive the data upon which this 

 calculation is founded. Were we to reckon a degree of mean 

 latitude 70 miles, which is considerably above the truth, the 

 distance between the equator and the pole would only amount 

 to 70 x 90 = 6,300 miles, which is not much more than a sixth 

 of the distance stated by Mr. Greenough. The length, of a 

 meridional circle, surrounding the globe of the earth, and passing 

 through both poles, does hot much exceed 25,000 miles, or two- 

 thirds of the distance which our author conceives to exist 

 between the equator and the pole. 



3. With the bones of the elephant and rhinoceros are inter- 

 mixed those of the elk, gazelle, horse, ox, buffalo, animals whioh 

 inhabit northern climates. 



4. Granting the debacle to have been occasioned by the 

 sudden elevation of the Moluccas, &c. no reason can be assigned 

 why it took a northern rather than a southern direction. 



5. The rising of these islands would have been inadequate ta 

 have produced the effect assigned by Pallas. 



