Pa UT II .] Troup : Fissibility of some Indian (Foods. 
81 
longitudinal direction only, that is, in the direction of the axis of the 
log ; no tests were made by splitting in a direction at right angles to 
the axis, though such tests would form an interesting subject for future 
experiment. 
These longitudinal splitting tests were carried out in a radial as well 
as in a tangential direction, the blocks being specially cut so that one 
pair of sides was parallel to the radius of the log and the other at right 
angles to it. 
It was found by trial that when longitudinal splitting is carried out 
between the tangential and the radial dii'ection, the force necessary to 
split the block lies between that required to split in a tangential and that 
required to split in a radial direction, the actual relative splitting force 
(see section 4) approximating to the radial or the tangential splitting 
force according to the acuteness of the angle between the plane of fission 
and that of the radial or tangential surface respectively. Hence it was 
found sufficient to split in the radial and tangential directions only, the 
average relative splitting force being taken as the mean between the two. 
In most cases six tests were carried out with each sample (log) of wood, 
three in a radial and three in a tangential direction ; the results are 
tabulated in detail in the Appendix. 
For purposes of comparison the I'elative splitting forces of seasoned 
wood only ai’e taken, because not only can such wood be conveniently 
obtained in much greater variety than green wood, but it is more 
constant as regards moisture percentage, which affects fissibility to a 
considerable extent, the percentage of moisture in green wood varying 
greatly according to the time the wood has lain after felling ; further it 
is not always possible to obtain absolutely fresh-felled wood for testing 
purposes. In the case of 16 woods, however, tests have been carried 
out with green wood, while specimens cut from the same log and 
allowed to season thoroughly were also tested for comparison. The 
results are somewhat surprising, as they effectually contradict the accepted 
theory that green wood splits more easily than dry wood. 
Dm-ing these splitting tests special note was taken of the manner in 
which the various woods were affected by the splitting, particularly as 
regards grain and surface ; these observations are recorded in the remarks 
column of the Appendix, while Plates I and II show various types of 
surfaces produced by splitting, references to which are made in the 
remarks column of the Appendix. 
B 2 
