Mr. Warington on some Specimens of Green Glass. 579 



foul, greasy, or soapy water; but on examination this was 

 found not to be tiie case, the surface of the glass having been 

 evidently affected by the action of some corroding agent. 

 Portions of the glass were therefore submitted to the action 

 of a weak solution of tartaric acid, as the acid most likely to 

 be present in wines; and in the course of twenty-four hours, 

 the vessel, in which the digestion was conducted, was one- 

 fourth part full of beautiful crystals of bitartrate of lime. It 

 was also strongly acted upon by diluted hydrochloric acid, 

 forming a solution of chloride of calcium, and a gelatinous 

 mass from the hydration of the silicic acid. From these pre- 

 liminary experiments it was evident that a great excess of 

 lime had been employed in the manufacture of the glass, 

 and this had rendered it totally unfit for any of the ordinary 

 purposes to which such bottles are applied. The glass was 

 then submitted to analysis, and as the routine followed, in 

 this and the subsequent case, was similar to that adopted 

 in the examination of all such compounds, I shall not detain 

 the Society by going through the detail ; suffice it to say, that 

 the alkalies, soda and potash were separated by the fluoric 

 acid process, and the potash estimated from the weighed quan- 

 tity of the mixed sulphates thus obtained, by means of the 

 double chloride of platinum and potassium. 



The results, calculated to the 100 parts, are as follows : — 



Silica 4900 



Lime 24-75 



Soda 7-25 



Potash 200 



Oxide of iron lO'lO 



Alumina 4*10 



Magnesia 2*00 



Oxides of copper and manganese a trace 



99*20 



On making additional inquiries concerning these bottles, I 

 found tliat they were offered to the consumer, the wine-mer- 

 chant, at a lower price than the ordinary wine bottles, and 

 that the vendors urged strongly the superiority of their goods 

 under the recommendation that they caused port wine to de- 

 posit its crust much sooner and firmer, that is, adhering more 

 tightly to the bottle, than would be the case where the com- 

 mon glass was employed. One gentleman had been a loser 

 to a considerable amount from bottling a large quantity of 

 white wine in these vessels, the bottles having become clouded, 

 and the flavour of the wine, as a matter of consequence, being 

 materially affected. As it was a question of scientific interest 



2 Q2 



