532 Tbansactioa^'s of the American Institute. 



the strength aucl permanence of a mortar depends on the impurities 

 of the lime. 



Mr. H. B. Smith, of "Westfield. — I have been devoting much 

 attention to this subject, with a view of ascertaining the cheapest 

 material for farm structures. At present I know of no concrete 

 that can be made cheaper than a brick wall. With brick at ten or 

 twelve dollars per thousand, and stone at the common prices, the 

 farmer can do no better than to use them. In Milwaukee, and many 

 Western towns, they are using, with great satisfaction, a combina- 

 tion of brick with the common lumber frame. This saves weather- 

 boarding, and a lower grade of lumber can be used with brick. 

 It is found about as cheap as the frame building, and superior 

 to it. 



Mr. S. Edwards Todd. — Mr. Inues thinks his plan is much 

 cheaper because rough workmen can be used. He makes a two- 

 sided box, as long as the height of his house, and fills it with con- 

 crete. These concrete sections are then set up side by side on the 

 sill and fastened together. The outside and inside are then plas- 

 tered, openings being left for windows and doors. I do not speak 

 of his plan as recommending it, but simply as stating what he 

 claims for it. 



IVIr. Deihl. — In traveling in the East, I observed in the ruins of 

 Baalbec, and at Babylon and the Tower of Babel, specimens of 

 concrete that must be over four thousand years old. They are as 

 firm to-day as when first erected. This shows us that the compo- 

 sition of a first-class concrete is one of the lost arts. The ancients 

 excelled us in this. 



Mr. A. S. Fuller sjave an instance of a concrete wall built for 

 Delmonico, that fell down at the first hard frost, and the judg- 

 ment of the Clul) is that no concrete walls can be recommended 

 as equal in cheapness and durability to both the materials gene- 

 rally used. 



CEMENT WATER-PIPES. 



Mr. S. M. Daboli. — About one bushel of cement to two of sand 

 will make a strong pipe. The sand should be sharp and coarse 

 and well washed. A good way to wash sand is to place the sieve 

 box in a stream of running water, put the sand in this box, and 

 stir it with a hoe. INIix the cement and sand thoroughly, in a dry 

 box, before wetting. Wet a small quantity at a time, and clean 

 out the box thoroughly before wetting a second box full, for small 

 pieces left will partially harden in a short time, and if these are 



