complete the equipment of the city, are large sales palaces, 
such as are to be found in European manufacturing centers, 
for the display of glass and other manufactures, the whole 
year round. Such modern methods of display would 
attract buyers from all over the country and from foreign 
countries. 
MANUFACTURE OF GLASS 
It has been said by an eminent authority on the sub- 
ject, that glass is a compound of various elements chem- 
ically combined, and yet it is not a true chemical compound, 
for the reason that it is not combined in definite proportions, 
as are many other chemical compounds. We may say, 
in short, that glass is but little more than vitrified sand. 
If we could obtain a temperature sufficiently high, we 
could make glass from sand alone. That this is not done 
in practice is because of the difficulty of getting a tem- 
perature sufficiently high to vitrify the sand, and also 
for the reason that we could not get vessels that would 
withstand the heat. 
Nothing short of the intense heat of the electrical 
furnace will melt sand alone. So to make glass com- 
mercially we are obliged to use an alkali in connection 
with the sand to be able to flux or vitrify it in an ordinary 
temperature, or such as can be maintained with the ordi- 
nary fuel at our command. In practice we use an alkali— 
preferably, carbonate of soda or potash. In connection 
with these two materials we have to add for a base, either 
lime or the oxide of lead. We use the nitrate of soda 
because it also has high fluxing properties, and has a tend- 
ency to make the “batch,” as we term it, boil; or, in other 
words, to set up a violent agitation which facilitates the 
melting. So we can say that ordinary glass is a double 
silicate of soda and lime; or, if we make the finer qualities, 
in which we use potash and lead, in that case it is a double 
silicate of potash and lead. So that sand, or, technically 
speaking, silicic acid, with lime and nitrate of soda, are 
the main constituents of ordinary glass; while sand and 
potash, with the oxide of lead. are the main constituents