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to put them one after the other in order to obtain the de- 

 aired thickness. In any other case, it would be equally 

 easy to arrange the lengths, breadths, and thickness of 

 this kind of stone. Thus, a stone ten inches long, could 

 oe only five wide and five inches thick to make up, and if it 

 jvas fourteen inches by seven, three inches thickness would 

 De enough, in order not to exceed too much the prescrib- 

 ed weight of 20 to 25 pounds. For partition walls, small 

 pise" stones of four inches thickness, by such length and 

 breadth as would suit. Now that the size and weight of our 

 pise stones are settled, we will goto work in the following 

 way, viz : we will first make strong moulds, having the 

 prescribed lengths and breadths in the clear, and a height 

 at least double the thickness the stones are to have ; 

 those moulds ought to be of good wood, well made and 

 well mortised, in the same way as moulds for bricks. 

 They must be filled with suitable fine earth, and struck 

 off" smooth without pressing it even with the upper sur- 

 face of the mould. Next, press the earth tightly with 

 the hand, then with a block fitting exactly the inside of 

 the mould, compressing it to half its size either by means 

 of a lever-press, mall, or other process that may be con- 

 venient. Such are the means pointed out by Cointereau, 

 which are very easy to be understood and executed. 

 What is more difficult is, after having pressed the block 

 down sufficiently to reduce the brick of pise" to the de- 

 sired thickness, to take out the brick easily, as it often 

 sticks very hard in consequence of the great compression. 

 In order to accomplish this, recourse must be had to all 

 the means employed in brick-yards in similar cases ; 

 sand or earth very fine or very dry must be used. Be- 

 fore putting the earth into the moulds, the inside of the 

 mould, the table upon which it is pressed, and the bot- 

 tom of the block, must be well sprinkled with the drj 



