XXXIX. ] PRODUCE AND WASTE. 335 
“Well-squared timber,” as understood in the trade, 
is nearly die square, and admits of little wane on the 
angles at any part of the log. The yield of this is 
about °68 per cubic foot of raw material, as shown in 
the table against Tewart. Some woods, when exceed- 
ingly well squared, will often yield a little more; as 
Mexican Mahogany. Others again, which are imper- 
fectly manufactured, yield considerably less per cubic 
foot ; as African. 
The figures against Oak, English, were obtained from 
the conversion of both “ rough” and “ sided,” not square 
timber. Also the figures against Elm, English, were 
obtained from “ rough,” and not square timber. 
The results given in the table were obtained from 
the conversion of timber for ship-building at Woolwich 
Dockyard. For civil architecture and engineering 
purposes the yield per cubic foot would probably be 
better, as there would be less waste in cutting to straight 
than to curved lines. 
The advantage of the table will be manifest on trial, 
since, if the figures in column A, which stand against 
any one of the woods mentioned in the list, are used 
as divisors of the net quantity of converted timber 
material required for any purpose, the quantity of hewn 
or square timber, z.¢ raw material, which it is necessary 
to purchase to produce it, is readily found. 
Example :—If 5,600 cubic feet of converted timber 
material (Dantzic Fir) are required, how much hewn 
or square timber will it be necessary to purchase to 
produce it ? 
In column A, against Dantzic Fir, is -700; therefore 
32 — 8,000 cubic feet. 
Also, if the figures in column A are used as 
multipliers, the converted produce can be ascertained 
