UTILIZATION OF CALIFORNIA EUCALYPTS. 15 
In a series of tests on hickory, now under way by the Forest Service, 
the average modulus of rupture of several kinds in a green condition, 
including pignut, shagbark, mockernut, big shellbark, nutmeg, and 
water hickory, runs from 9,200 pounds per square inch for nutmeg 
hickory, which is considered an inferior variety, to 11,450 pounds per 
square inch for pignut. For comparison with these figures, blue gum 
has an average modulus of rupture for green material of 11,800 pounds 
per square inch, or slightly larger than for pignut hickory. The dry 
weight per cubic foot of blue gum is about 49 pounds. The average 
weight of oven-dry pignut hickory is about 51 pounds per cubic foot. 
OTHER SPECIES.” 
Table 3, arranged in the same way as Table 1, gives the results of 
tests on the four eucalypts, red gum, sugar gum, gray gum, and 
manna gum. Green sugar gum is seen to have strength values con- 
siderably above the other species. It has an average bending strength 
of 16,480 pounds per square inch and an average crushing strength of 
7,215 pounds per square inch. Red gum (shipment 73) comes next 
in strength, with an average modulus of rupture of 12,570 pounds per 
square inch and an average crushing strength of 6,047 pounds per 
square inch. Shipment 14, also red gum from a different locality, 
is considerably lower in strength than shipment 73. Manna gum 
(shipment 9) shows the lowest strength values of the four species, 
although shipments 80 and 83, also manna gum, have strength 
values slightly above the weakest of the two red gum trees. Gray 
gum (shipments 68 and 77) occupies an intermediate position in 
regard to strength. 
[Cir. 179] 
