fl6 Proofs from old English Boohs, that the 



confess that this exaltation of the antient geometricians, on 

 such grounds, reminds me of the folly of those fanatical pe- 

 dants, who maintain that the elements of all the arts and sci- 

 ences, are to be found in Homer. No worse a judge than 

 Huygens was of a very different opinion. " If any particular 

 person (says that great man) had been so diligent and saga- 

 cious as to invent this instrument from the principles of 

 nature and geometry ; for my own part, I should have 

 thought his abilities were more than human. But the case is 

 so far from this, that the most learned men have not yet been 

 able sufficiently to explain the reasons of this casual inven- 

 tion." These are the. words of Huygens, as translated from 

 his Dioptrica by Dr. S.*, who seems to have forgotten 

 them when, merely from some errors in theory, he con- 

 cludes that Roger Bacon was unacquainted both with spec- 

 tacles and telescopes. Nor doe3 he seem to have recollected 

 that a 6i casual invention" might as well have been made 

 by Bacon, or some other philosopher, in a dark age, as by 

 .Tansen and other ignorant men in an age more enlightened ; 

 an argument which w r ould no doubt be equally strong in 

 favour of the antients, if they had left us as strong proofs 

 of optical knowledge, as Bacon has. 



20. Dr. S. being, as far as I know, the only respectable au- 

 thor f who has seriously disputed Bacon's pretensions, against 

 the judgment of Dr. Plott, the two Molyneuxes, Dr. Jebb, 

 *Dr. Friend, Muschenbroek, and other learned men %, I should 

 here hazard a few pretty close remark's on his arguments, if 

 I were in possession of the Opus Majus, whence he quotes 

 the passages from which he endeavours to justify this sin- 

 gular opinion. That work of Bacon cannot be very scarce, 

 as it was published among that philosopher's works, by Dr. 

 Jebb, in 1733 §; but it is probably immured in our public 

 libraries, to which ordinary men cannot have any easy or 

 useful access || ; for I have never seen it, or met with any 



one 



* Compleat System of Optics, Remark 103, e.t scqq. 



+ See Mr. Bonnycastle's excellent translation of Bossut's Hist. de. Ma- 

 themaiiqttes, p. 189, and Dr. Mutton's valuable Dictionary, art. Tela cops. 

 - * Among v.'i'om we may reckon Dr. Campbell, who (as appears from 

 an adveitisemcnt by his amanuensis, cut out of a newspaper and pasted 

 into the first volume of the B.o^rapbia Britannica, first edition, 1747* 

 now before me) drew up all the articles marked E and X in that work. 

 The arricle Ba on (Rog,r), on which the learned compiler has bestowed 

 grc.it labour, is marked S. 



§ Sec Biog. Britann., article Bacon (Roger). 



(j. For example, a few months ago, an advertisement appeared in the 

 public prints, stating that papers were to be delivered at the porter's lodge 

 of the British Museum, showing the manner of applying for admission to 

 i the 



