mgi On the fafchia ting Facultv afcrihed to 



You Inform me, that my explanation of the fuppofed faf- 

 cinating faculty of ferpents is adopted by many of your na- 

 turalifts. This is pleafing to me. Indeed, fuch is our felfifh- 

 nefs, that I fear I ihould have felt fomewhat gratified to learn 

 that the theory had been adopted, though I myfcif had re- 

 linquifhed it. But I alTure you that, as yet, I have feen no 

 caufe to rclinquifh it. On llie contrary, I poffefs a great 

 body of additional fails in fupport of it, Thefe fafts will be 

 carefully adduced in that part of my Fragments which is in- 

 tended to comprife the hidory of the amphibia of PennfyU 

 vania. 



In my native country the explanation which I have of- 

 fered has been adopted by many perfons. But there are 

 others who ftill believe in the exiltence of a true fafcinating 

 faculty in the rattlefnake and other ferpents. What change 

 time and further attention to the fubjeft may accomplifh m 

 them, I know not. But why fhould we expeft to make all 

 philofophers converts to our opinions? Almoft every phse- 

 nomenon, almoft every faft in nature, feems to admit of an 

 explanation upon more than one prmciple. The dream ot 

 inquiry is often diverted by trifling circumftances into very 

 oppofne direftions. Prtjudices, or, to name them by a 

 milder phrafe, the earlier biafles of our minds, frequently 

 detain us, in the inveftigations of fcience, in a long and 

 pleafing reign of tyranny. Our firft love is faid to be the 

 ilrongeil. Our firft principles in fcience, in religion, and 

 in politics, are often adhered to with the extreme of pertina- 

 city. He who, turned of fifty years of age, relinquifhes a 

 favourite error, has infinitely more merit than the world may 

 be willing to allow him. 



I beg you, fir, to make what nfe of this letter you may 

 think proper. If it fliall add any thing to the ftock of your 

 knowledge on the fubjed, or if it fliall I'erve to amufe you in 

 an hour of ieifure, I Oiall feel hiszhly gratified. 



Be allured that I am, with very great refpeft, 

 . ' Dear fir, your faithful and obliged 



fcrvant and friend, 



Benjamin Smith Barton, 



postscript. 



I BEGAN this long letter on the very day that T firft faw 

 Mr. Blumenbach's remarks in Tilloch's Magazine. I had 

 not finiflied it before I received a copy of the original publica- 

 tion of the profelVor. In the conclufion I find he urges me 

 to extend my inquiries into the real w^n of the crepitaculwri, 

 Cauda, or rattle of the crotalus. This is certainly a queftion 



worthy- 



