AMERICAN INSTITUTE. 



*199 



sand into a ridge; the roller D spreads this ridge out, piressing 

 the lime and sand particles together into intimate union, and at 

 the same time the hind end of the drag has a wab])ling motion 

 given to it by the bar G, throug'i wheel W, on which it is set ec- 

 centrically. It is thus that the lime and sand receive a mixing 

 together of a more thorough character than by hand labor. Un- 

 less every particle of sand is enveloped with a coat of wet lime 

 the mortar is not perfectly mixed. By hand labor this is seldom 

 if ever effected. It is evident that such a result is easily obtain- 

 ed by working a sufficient length of time in this machine. After 

 the materials are thoroughly mixed, and the mortar properly 

 formed, the trap door, F, is shut down, the drag then gathers the 

 mortar formed into a heap, if desired, or pushes it down into the 

 receptacle described, through a trap door in path A. The lime 

 employed is previously slacked before it is put on the way, A. 

 A few revolutions of the roller and drag mixes the materials. 



We are informed that with the labor of one man and a horse, 

 thirty casks of lime can be made into plastering or building mor- 

 tar by it in one day, and that the mortar is of a very superior 

 quality. It works as smooth as fine cement under the trowel, and 

 it sets and hardens much sooner than common mortar. 



[.^ diploma awarded. 



'•{/'"'^^f^ 





M^m^^ ^ 



Fairbank's Rail Road Scales. 



Rail Road Scales. 



Fairbanks k Co., 189 Broadway. The platform scale, which was 

 unknown a third of a century ago, has now become an indispens- 

 able article to every mercantile and ma^iufacturing estahlishment 

 W^here business is transacted by weight. It has entered into near- 

 ly^every department of trade. It is used to ascertain the quan- 

 tity of many articles of merchandise, as grain, coal, &c., which 

 w^ere formerly either measured in detail or imperfectly estimated 

 in bulk; it has almost entirely superseded otlier and more clumsy 

 contrivances for weighing, and recommends itself by its conven- 



