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THE POPULAR SCIENCE MONTHLY. 



If formed of cement, they must have time to harden, and for that 

 purpose must be removed from the mould on which they were formed, 

 to prevent cracking by contraction; and here the cloth bandage be- 

 comes a necessity. But this cloth is a costly article, requiring a great 

 expenditure of hand-labor and time. It must not be allowed to fasten 



Fig. 5. 



to the vessel as the cement hardens. To prevent this, a simple, natu- 

 ral device has been adopted. The pottery shows a laminated texture. 

 No doubt every fresh layer of the cement has been hardly compressed 

 on the previous one; for at hand we find the primitive tools that were 

 used for the purpose, scattered over the site of this ancient pottery- 



