CTiii Vrogrffi of the Royal Society of London. 37 



Their experiments on the freezing of water in different 

 circumftances ; on the produftion of cold by lliline folutions; 

 Cn ice, to evince that it was I'ufceptible of various degrees of 

 cold more intenfe than thr.t of fimple freeziii<r; and on the 

 congelation of oils; were various, interefting, and profecutcd 

 with the molt attentive accuracy. A curious train of expe- 

 riments was made at the Tower, under the immediate iufpec- 

 tion of the lord vifcount Brounker, to afcertain what changes 

 might be produced on the weights of lead and copper by fub- 

 jedtion to fire in a cupel. Both the copper and the lead 

 were found to gain (by oxidation, no doubt,) an addition. 

 The cupel fuffered always a diminution of its weight when 

 ignited, but not a diminution equal to the augmentation in 

 the weight of the metals. 



Among the inftrumcnt? invented by the fociety within f 

 few years after its inftitution were, an univerfal (t.q'"''*t'"u 

 meafare of magnitudes iiv means of the pendulu'-"^ a wneel 

 barometer, and other inliruments, for iindi'^ l^'^r P'"^!''"''^ ^f 

 the air; an auger for borinjj the grou--',^"". tetchmg up 

 parts of the flrata through uhich ^ ^"0"1J pa'^m their na- 

 tural order; an inflrumei-' hv nieafurmg the Iwiftnefs and 

 ftrentrth of the wind,- i diving-bell, and a pan- o\ fpeftacles 

 with°which a diver might fee any thmg diilmftly under 

 water; fcveral enfrines f"r finding and dclermuiing the force 

 of (Tunpowdcr ; fvn-eral acouftic inllruments to aflift and im- 

 prot-c the fcnfe of hearing; admriot ■zvuv-wijh; whicli would 

 exaaiy mcafure the lentil, of the way of any coach or chariot 

 to which it was applied ; an inllrunient for grindmg optical 

 glalTes; a varietv of telcfcopes, ?cc. 8:c. 



A manufacture of olafs had been, more than thirty years 

 before, eftabliflicd in Broac'-lireet, in London, by a company 

 of mercantile adventurers, among whom the moft confider- 

 able perfou was admiral Sir Robert iManfcI. 'Workmen and 

 liipcrmtendents were pr»cured from Venice. It might; have 

 <-oiie on fuccefsfullv, if -he great civil war had not broken out. 

 Soon after the reitorabon, the duke ot Buckingham, at a valt 

 expenfe, eftabliflicd rew glafs-works in London; and the art 

 was there, within a very few years, carried to fuch perfec- 

 tion, that thefe worl-s fupplied better glul's for microfcopes and 

 telcfcopes than tha! which was to be had from Venice. The 

 duke of Buckinirliam not only expended much money upon 

 ihofe glafs-workl. rather as an experimentalilt than a manu- 

 facluror, but took a warm and aftive interell in various others 

 bf the focictv's nurfuits ; and it was under his immediate pa- 

 ' C 3 tronage 



