204 



Mr. T. Gray. 



Specimen IV. (Japanese lime glass tubing.) 



C. 



113xlO n 



25 x 10 11 

 61 x 10 10 



26 x 10 10 

 12 x 10 10 



499 



Silica 57*2 



Potash 21-1 



Lime, &c, by diff. 16 7 



100 -o 



The analyses of the last two specimens are only approximate, 

 having been made previous to the electrical experiments, and for a 

 different purpose. The composition differs very widely from that 

 which is required for a pure silicate, and the electrical resistance is 

 also found to be very low. 



Specimen V. (French flask.) 



45° C. . 



327 x 10 10 . 



. 2 533 . 





70 -05 



55 



133 x 10 10 . 







10 -33 



65 



509 x 10 9 . 





Lead oxide 



2 70 



75 



. 204 x 10 9 . 





Soda 



14 -32 



86 



. 812 xlO 8 . 







1 44 



95 



. 391 xlO 8 . 







o-io 



108 



. 133 xlO 8 . 





Alumina, iron oxide, 





117 



. 707 x 107 . 





manganese oxide . 



1 -45 



100-39 



With regard to this specimen, Dr. Divers writes as follows : — 



" This seems to be a soda lime glass mixed with a little potash lead 



glass ; the latter having been thrown in as cullet. Assuming this to 



be the case, we will have approximately — 



Potash lead glass 8 "7 



Soda „ 91-3 



100 -o 



The soda lime glass has then the composition — 



72-7 

 11 4 

 15 -9 



Silica 

 Lime. 

 Soda . 



100 -o 



