G LA 
■ An abfervation of optic glaffes made of rock 
cryftal - - Divini 
. ■ An account of the invention of grinding optic 
and burning glaffes of a figure not fpherical 
- - Smethwick 
— Method of polifhing telefcopical glaffes by a 
turn-lathe ; as alfo the making of an extraor- 
dinary burning glafs at Milan - Anon, 
— The defcription of a way laid to be new and 
univerfal, for working convex fpherical glaffes 
upon a plane for all practicable lengths, without 
other difhes or concave moulds Mancini 
• The generation of an hyperbolical cylindroid 
demonftrated, and the application thereof for 
grinding hyperbolical glaffes hinted at Wren 
A defcription of Dr. Chr. Wren’s engine de- 
figned for grinding hyperbolical glaffes, as it 
was in a manner promifed, vol. III. p. 962 
- Wren 
— - — The effects of the different refractions of the 
rays in telefcopical glaffes - Anon . 
A fure and eafy way to make all forts of great 
telefcopical glaffes, with a generous offer of 
furnifhing induftrious affronomers with them 
- Rcrelli 
.. ' Letter about the making of microfcopes with 
very (mail and {ingle glaffes, and of forne other 
inftruments - Butterfield 
. A dioptrick problem why four convex glaffes in 
a telefcope fhew objets eret Molyneux 
— A way for myopes to ufe telefcopes without eye- 
glaffes ; an object becoming as ufeful to them, 
and fometimes more, than a combination of 
glaffes - - Defaguliers 
— • A new method of improving and perfecting ca- 
tadioptrical telefcopes, by forming the fpecu- 
lums of glafs inftead of metal Smith 
*— Letters relating to a theorem of Mr, Euler, for 
correcting the aberrations in the gbje&'-glaffes 
of refracting telefcopes; by 
- - Shorty Euler , and Uollond 
— — A report concerning the microfcope glaffes fent 
as a prefen t to the Royal Society by father 
Torre of Naples * - Baker 
A method of working the objedf glaffes of re- 
fracting telefcopes truly fpherical Short 
Glass. j( Natural Philofophy), An account of an expe* 
Dda 
Tranf. 
— 362 
HI 631 
— 795 
III 837 
IV 961 
— I0 59 
VIII 6086 
XI 691 
XII 1026 
XVI 169 
XXX 1017 
XLI 326 
XLVI 1 I 287 
LVI 67 
LIX 507 
v 
Abridg. 
~ *95 r 
— 194 
I 188 
— 189 
~ 156 
— 195 
— 208 
— 189 
IV 188 
VIII 1 13 
♦ 
: l - 
riment 
