42 
TIMBER AND TIMBER TREES. [chap. vii. 
unnecessarily weakening those which remain. There 
are, undoubtedly, many examples to be found where 
larger scantlings have been experimented upon, and 
the results of these are, of course, more reliable and 
trustworthy. 
The tests for the transverse strength in my experi¬ 
ments were conducted, in every case, with pieces 
2" X 2" x 84 // =336 cubic inches. Each piece was placed 
upon supports exactly 6 feet apart, and then water 
was poured gently and gradually into a scale suspended 
from the middle until the piece broke, note being taken 
of the deflection with 390 lbs. weight, and also at the 
crisis of breaking. 
After this a piece 2 feet 6 inches in length was taken, 
wherever it was found practicable, from one of the two 
pieces broken by the transverse strain, and tested for 
the tensile strain by means of a powerful hydraulic 
machine, the direct cohesion of the fibres being thus 
obtained with great exactness. Further, for the purpose 
of determining the proportions of size to length best 
adapted for supporting heavy weights, a great many 
cube blocks were prepared, of various sizes, as also a 
number of other pieces of different form and dimensions, 
which were then, by the aid of the same machine, 
subjected to gradually increasing vertical pressure in 
the direction of their fibres, until a force sufficient to 
crush them was obtained. 
