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facing of the artificial stone. Diro"t compression of the 

 face should be obtained. If coloring matter is used only 

 mineral colors should be used. 



Tests: Tests should be made on 28 day specimens to 

 determine the character of the sand, gravel or broken 

 stone. 



Body of Stone: The body of the stone should be made 

 of a 1:2:4 mixture of an established brand of Portland 

 cement, clean sharp sand and gravel or stone passing 

 through a % in. ring. Enough water to insure a good 

 bonding mixture should be used. 



Laying: Before laying the various pieces the adjoin- 

 ing work should be thoroughly moistened so as to prevent 

 absorption of the water out of the mortar. This mortar 

 should be composed of 1 part cement, 3 parts of sand and 

 1 part of slaked lime. If the stone is cast in place the 

 forms should be sandpapered, shellacked, sprinkled and 

 oiled, a 1:2 mixture % in. thick placed next to the forms 

 and the backing of a very wet 1:2:4 mixture then added. 

 Troweling should not be allowed on the face, as checks 

 and hair cracks would result. 



Corners, etc.: All corners and edges shall be sharp and 

 well defined. They shall have true horizontal or vertical 

 lines, and no stone will be accepted that is chipped or 

 marred in any way. Where the corners or edges are apt 

 to be struck a piece of galvanized iron bent in the shape 

 of a written small i shall be used. 



Reinforcement: When pinnacles, base courses, balus- 

 ters, railings, etc., shall be liable to crack, due to shrink- 

 age stresses, the same should be reinforced by the proper 

 amount of steel to prevent such cracks. 



Discoloration: All artificial stone should have a uniform 

 color and should be made of such cements that there will 

 be no efflorescence. Cement of the same color only should 

 be used to prevent streaking. The sand should also have 

 the same shade of color. 



STANDARD SPECIFICATIONS FOR CEMENT. 



General Conditions. 



1. All cement shall be inspected. 



2. Cement may be inspected either at the place of 

 manufacture or on the work. 



3. In order to allow ample time for inspecting and test- 



