On the Vurm of Spectacle- Glasses. 65 



inachinciy. The steam-engine was re-discovered by Thomas 

 Savery, Esq. treasurer to the Sick and Hurt Office ; and the 

 telesrraph (the saiiject of the manjiiis's sixth and sevcntii ar- 

 liclesi) bv Dr. Ifook, as has been already proved *. Bat most 

 of that great coHcction, it is to be feared, will ijiig i ^mam 

 undiscovered, — monuments alike of the '.uarquis's superior 

 genius, and of the barbarous stupidity of his coieinporarieS 

 in neoloeting such a treiisure. 



*^* Should the reader observe that I have taken. no notice 

 of bishop Wilkins in what I have said of sub-marine navi- 

 gation, I can only say, that thcnigh the. Matheniaiicai Alagio 

 v\as lying before me, I unaccountably overlooked it, till the 

 printer liad advanced' too far to atimit its bem<; quoted in the 

 proper place. But this onnssion i^ of the less consequence, 

 as the fifth chapter of the bishop's second book, which is 

 employed on tliat subject, is chiefly speculative and hypo- 

 thetical, some part of it indeed extravagantK' so. I must 

 except this feeuteuce — " That such a contrivance is feasible, 

 and mav be effected, is beyond all question, because it hath 

 been already experinjcnted, here in England, by Cornelius 

 Drcbell." This positive assertion of bishop Wilkins is of 

 the more importance, as DrebcH's experiment was probably 

 made in his own life-time ; for he was born in 1C14, above 

 twelve years before Mr. Boyle'f, and within the limits of 

 king James the first's reign (\603 and lt)25), when that ex- 

 periment w^as made. 



When the above was almost printed oflf, I lighted on a 

 quotation from an old author, which threatens to d'-prive 

 Napier of the priority of his proposal for exciting couibus- 

 tion by the solar rays ; and two passages, which will tend to 

 give us new views of the invention of the telescope. But 

 probably your readers, as well as myself, have enough of 

 such subjects for the present. *D. 



Vni. Ol<servui'mi<; on Dr. Wollaston's Statements re- 

 specting an Lnjjrovenient in the Form of Spectucle- 

 (Jlasses. /j// William Jones, Esq. F.Ani. l\ S. Op- 

 tician, Jvdborn. 



OnsERViNG, in your Magazine for last month, that Dr. 

 n. W'ollaston, by a paper inserted therein, is attempting to 

 iiilroduee into the construction of spectacles, the well-kuown 



• Phil. Mat', vo!. i. 



+ S'.-e Or. Hutr.in's Diftionary, a-ricles Boyle and WtlUns. 



VoL.XVIII.No. Cy. E and 



