The British Guiana Exhibition. 105 
tice. But, according to Mr. Barclay, the trees yielding 
samples 2 and 4 are not plentiful ; they may be dismissed, 
therefore, without further comment. Sample 1 contains 
a fair quantity of tannin, but yields a dark and ill- 
coloured leather, while the chief objection to sample 
5 is the moderate amount of tannin present. Both 
these barks, however, can be obtained in large 
quantities, and are, no doubt, worth attention. The 
remaining samples, 10 and 13, appear to be excellent in 
every respect and deserve a strong recommendation for 
trial. They contain a very fair amount of tannin, and 
the leather they yield is exceptionally light coloured — 
that from sample 13 being the better in this respect. A 
partial analysis of these barks gave the following results : 
10. 13. 
Water ... ... ... ... 12-67 13-27 
* Portion soluble in water ... ... 24-50 17-70 
Ash ... ... ... ... 2-23 4-83 
Woody matter ... ... ... 60-60 64-20 
100-00 100-00 
* Containing tannin ... ... ... 11-32 9-44 
Although the bark of the black mangrove {Rhizophora 
mangle) is not comprised in the samples collected by 
Mr. BARCLAY, yet, I may mention, it should hold a high 
place amongst the tannin materials of the colony. Pro- 
perly used it tans with great rapidity and it contains a large 
percentage of tannin as the following analysis shows : — 
Water ... ... ... ... 13.33 
* Portion soluble in water ... ... 33-53 
Ash ... ... ... ... 5-48 
Wood matter ... ... ... 47.76 
100-00 
Containing tannin ... ... ... 15.76 
O 
