THE GAT ALP A. 



Prof. (J. S. Sargent, of the Arnold Arboretum and Botanic 

 (lardens of Harvard University, has kindly furnished the fol- 

 lowing paper : 



E. E. BARNKY, ESQ.: 



X/r: 1 have examined with much interest the various speci- 

 mens of catalpu wood, with which you have favored me at 

 different times. 



1 find that the specific gravity of the wood of the common 

 ('nhtlfHi bignonioides is, when perfectly dry, .405; and that the 

 specific gravity of the wood of the early blooming variety, also 

 perfectly dry, is .462.* The ratio of weight of any wood to the 

 weight of an equal body of water, that is its specific gravity, 

 gives in many respects the surest indication of its value for 

 construction and fuel. But to show the relative value of catalpa, 

 it will be well to compare its specific gravity with that of some 

 better known or standard woods. 



Specific gravity of common Catalpa. .405. 



>L early blooming Tata! pa, .4<VJ. 



- Eastern Hickory. ..X/JX. 



White Oak, .WL>. 



" American Elm, .649. 



" Rock Elm,t .832. 



Black Walnut, .577. 



" " Canoe Birch, .5:> ( J. 



u Wild Cherry, .488. 



" Ailanthus. ' .614. 



By this comparison it will be seen that catalpa is inferior 

 in weight, and consequently in strength and heat-giving qual- 

 ities, to even such soft woods as the black walnut, the canoe 

 birch, or even the wild cherry, which up to this time is the 



-Tlic.s*- sp.-citic LM-iiviti.-s h:-iv.- I n ml'-ulnt.-.! l.y Mr. S. P. Slmrplrs-, St:it.- As^;iy..-r of 



Massachusetts. 



f Uhnuis rncemosa. Thomas. 



