243 



work in collaboration was soon unavoidably interrupted. We 

 present here very briefly, however, such of our notes in this con- 

 nection as may be of general interest. 



Elementary composition of heart-wood. — Elementary 



analysis of typical samples of (l) the red logwood of commerce (2) 

 a "bastard" variety somewhat resembling it and (3) a second 

 specimen of the " bastard" type yielding hardly any pigment to 

 water gave the following results : — 



Table I. 



Percentage elementary composition of saBSTANCE deied to constant 



WEIGHT AT 1 10°C.* 



Summary of averages. 



Carbon 

 Hydrog n 

 Ash 

 OxygenJ 



52-01 

 5-84 

 1 -86 



42-15 



II. 



51-56 

 5-96 

 1-63 



42 48 



IIL 



51 13 

 5 66 

 1-94 



43-21 



General Average. 



51-57 

 5-82 

 1 81 



42 61 



The most significant feature of these results is the decreasing 

 amount of carbon in the " bastard" wood. The differences are 

 too slight to warrant any emphasis, but are such as might be due 

 to a lower percentage of hematoxylin, which is a pigment of high 

 carbon (and low oxygen) content — C^^ H^^ 0„ 



The data of the second series of analysis, given in TABLE II, 

 show that the wood was not decomposed in the process of drying 

 to constant weight at 110° C. (first series) and that, therefore, the 

 previous results were not influenced by that procedure. 



General composition of seedlings. — In table III we pre- 

 sent the results of some analyses of seedlings of " red" logwood 



*Only heai-t-wood was etnployed in this work. This was converted into sawdust and 

 only such ijortions as pas-ed through a very floe sieve were taken for analysis. The 

 methods of analysis were those which are now in general use. 



t The figures for carbon and hydrogen are calculated (from the dataof direct analysis), 

 for ash-free suhstauce. 



X Calculated, by difference, for ash-free suiistance. 



