476 TRANSACTIONS OF THE AMERICAN INSTITUTE 



DRAIN PIPE. 



Prof. Seely exhibited a specimen of bitinniDized pipe. The 

 process of raaniifacture consists in causing a roll of paper to 

 pass through a reservoir of melted .bitumen, after which it is 

 tightl}^ coiled around a mandril to any required thickness. The 

 paper is so well protected by the asphaltum as not to be liable 

 to decay. 



Mr. Tillman. — Tlie same has been used for roofs, and does not 

 succeed. 



Mr. Stetson stated that the extremes of temperature and of 

 moisture and dryness to which a roof is subjected are very much 

 more deleterious to such a substance than the uniform exposure 

 of such a pipe used for water or gas. 



TYPE-SETTING MACHINERY. 



On motion of Mr. Stetson, 



Resolved, That a committee of three from the Section on 

 Mechanics be requested to examine and report to the Section on 

 type-setting machines, to which their attention may be called 

 with reference to the gold medal. 



Messrs. Bogardus, Ward, and Mason were nominated and 

 appointed as the committee, with power to fill vacancies. 



SOLUBLE GLASS. 



Prof. Seely stated that water-glass, or glass soluble in water 

 although made by accident several centuries ago, had not been 

 known until 1825, in its necessary conditions. To some extent 

 any glass is soluble in water. Those glasses which contain the 

 largest proportion of potash or soda, with but little lime or other 

 alkaline earth, are most readily soluble. It has been proposed 

 to use water glass as a covering for stone houses, to be applied 

 in the liquid form, spirting it on with a rose and to harden on 

 the wall. Applied in this way, it gives a very fine finish to plas- 

 tered walls. In a short time the surface assumes a brilliant 

 lustre, suggesting the idea of varnish. But after it is completely 

 dry it cracks and parts with its polish. What is called stereo- 

 chrome, is a process of covering walls after . coloring them with 

 this fluid, which fixes the colors and preserve their brightness 

 indefinitely. If water-glass is applied to a surface which has no 

 reaction, it is liable to be washed off. Applied to marble or to 

 a plastered wall, the silica leaves the potash and forms an inso- 



