40 
BULLETIN 1500, U. S. DEPARTMENT OF AGRICULTURE 
Temperature of Wood Before Gluing 
Because of the relation of temperature to the consistency of 
animal-glue solutions (fig. 7) and its effect upon the strength of 
joints (figs. 8 and 10) made with animal glue, preheating the wood 
before gluing is often inadvisable. Where the assembly time is long, 
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the wood cold, and the glue of high grade, a moderate warming of 
the wood may be necessary to prevent the glue from thickening 
excessively before pressure is applied. On the other hand, where 
the assembly time is short, as in most edge-joint operations (pi. 7, B), 
