170 ELEMENTARY FORESTRY. 
method, and requires very different management. The more 
nearly perfect the quarter-sawing is done the more waste there 
is, and so it is the object of practical men to avoid the extremes 
of perfect quarter-sawing (at great expense in labor and mate- 
rial) and through-and-through sawing (which is cheapest and 
most economical of material). In ordinary quarter-sawing of 
this kind there is a waste of twenty to thirty per cent in material 
as compared with through-and-through sawing. This waste is 
found in the feather edged pieces and bevelled edges which have 
to be cut off, and in the very narrow strips of no value. Small 
logs waste much more than large logs in quarter-sawing. Most 
sawyers place the minimum sized log that should be used for 
quarter-sawing at twenty-six inches in diameter. It is very 
important to have quarter-sawed lumber wide, as narrow stock 
is of comparatively little value. In ordinary sawing there are 
always a few cuts made parallel to the silver rays which have the 
desired quarter-sawed figure. 
In practice, several methods of sawing are used to bring out 
the silver grain. The most common is to quarter the logs, and 
then saw each quarter, as shown by the lines in Figure 45. 
FUEL VALUE OF WOODS.* 
“The Relative Fuel Values here given are obtained by 
deducting the percentage of ash from the specific gravity, and 
are based on the hypothesis that the real value of the combus- 
tible material in all woods is the same. 
“Tt appears from Mr. Sharples’ experiments that resinous 
woods give upwards of twelve per cent more heat from equal 
weights burned than non-resinous woods; the heat produced by 
burning a kilogram of dry non-resinous wood being about 4,000 
units, while the heat produced by burning a kilogram of dry 
resinous wood is about 4,500 units, a unit being the quantity of 
heat required to raise one kilogram of water one degree centi- 
grade. 
“Count Rumford first propounded the theory that the value 
of equal weights of wood for fuel was the same, without reference 
to specific distinctions; that is, that a pound of wood, whatever 
*This article on the fuel value of woods is taken from the “Report ot 
the Tenth Census,’ by Prof, C. S. Sargent. 
