By turning on a very free supply of gas, and only enough air to give an outward direction to the burning gas, a smoky flame, chiefly useful for annealing and for some simple operations on lead glass, is produced.
On the other hand, the fine-pointed oxidising flame of the Herapath blow-pipe is, perhaps, the most suitable for working joints of lead glass.
Its color is greenish blue in potash-lime glass, bluish green in soda-lime glass, and yellowish green in lead glass.
Nickel produces an amethyst color in potash-lime glass, a reddish brown in soda-lime glass, and a purple in lead glass.
Chromium produces a green color, which is reddish in lead glass, and yellowish in soda, and potash-lime glasses.
We have here a remarkably pure potash-lead glass, for only 0.
The one is a typical soda-lime, the other an equally definite potash-lead glass, and the materials had to be sought for from entirely different sources.
Formerly much apparatus was made of lead glass, but at present it is very seldom met with, except in the little drops of special glass used to seal platinum wires into the larger sizes of tubes.
Lead glass is softer and more readily fusible than soda glass, but has the disagreeable property of growing black in a few seconds unless worked in a strong oxidizing flame.
In general, when the soot burns off freely, or lead glass begins to show the faintest sign of reduction, or soda glass begins to colour the flame, it is more than safe to proceed.
Lead glass is yellow, soda glass is green, and hard glass purple in the samples in my laboratory, and I expect this is practically true of most samples.
The, work is exposed to this flame until, in the case of lead glass, traces of reduction begin to appear.
Nickel with a potash-lead glass gives a violet colour, and a brown colour with a soda-lime glass.
With the same object, red lead and saltpetre are used in the mixture for potash-lead glass.
The varieties of glass used for the manufacture of table-ware and vases are the potash-lead glass, the soda-lime glass and the potash-lime glass.
The above list will hopefully provide you with a few useful examples demonstrating the appropriate usage of "lead glass" in a variety of sentences. We hope that you will now be able to make sentences using this group of words.
