REPORT OF SOCIETY’S MEETINGS. 201 
TABLE VII.—Co-EFFIcIENTS OF ELASTICITY FROM BENDING TESTS. 
: Range of Elastic Co-efficient of 
“ a Stress, Deflection. Elasticity. 
‘e 5 Name. 
a Pounds per Pounds per| Tons per 
= sq. in. Inches, sq. in, sq. in. 
70 a | Greenheart 0 to 5846 1-436 2,874,500 1,283°4 
70 ec *s sed 0 to 6446 °2508 2,887,300 1,289°0 
71 a | Souari See mas 0 to 5515 *2640 2,353,600 1,050°6 
72 a | Lgt. Br. Cirouballi| 0 to 4282 *2936 1,640,300 732°2 
72¢ ” rr) 0 to 4167 “3160 2,469,200 655'9 
74 a | Kabucalli ... oe 0 to 4746 "4100 1,155,300 i bags 
The r= ree Sa 0 to 6696 “4128 1,858,300 829°5 
REPORT ON THE RESULTS OF PRACTICAL TESTS APPLIED TO TEN VARIETIES 
OF BRITISH GUIANA TIMBER. 
The timbers reported on were sent for the purposes of testing in 
March last, but as they were far too green for any reliable tests to be 
made with them at that time, they were kept in a dry place for six 
months, and were then broken down into 4-inch planks ; but being still 
too wet to furnish reliable resu!ts, they were kept for a further period of 
four months before being submitted to trial. Pieces of each of the logs 
were passed through various machines, and although still far from being 
properly seasoned, they were sufficiently so to allow of an opinion being 
formed as to their practical value for various purposes. Of theten logs, 
no less than seven already showed undoubted signs of decay, althoughs 
as above stated, they are not, even now, nearly as dry as they should be 
to be worked up for any practical purposes. The development of this 
tendency to rot so soon after the timber has been felled may be due to 
one of three causes: It may be owing (a) to the trees having been 
felled when full ofsap; or (2), to the timber having been grown in a 
marshy locality; or (c), to some inherent qualities in the wood which 
make them liable to rapid decay. Ifthe defeét in question is due to the 
first of the above causes, it could be remedied by felling the trees in the 
winter season, but if it is ascribable to either of the other causes men- 
tioned, it will be a serious drawback to the use, for any permanent 
structures, of such descriptions of timber as have already shown signs of 
decay. All these ten sample logs, without exception, were very easily 
worked by machinery, the hardest of them, viz., greenheart, being quite 
as easy to saw and plane as the average quality of English oak while 
the majority of the other samples are worked quite as easily as mahogany 
and cedar. The following remarks represent the results of the tests :-— 
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