130 
MR. BEVAN ON THE MODULUS OF TORSION. 
Table (Continued). 
Species of Wood. 
Specific 
gravity. 
Modulus of 
Torsion. 
Pounds. 
Observations. 
Crab ....... 
.763 
22738 
Damson 
23500 
Deal, Christiana . . 
.38 
11220 
Elder 
.755 
22285 
Elm 
13500 
Fir, Scotch .... 
13700 
Hazel 
.83 
26325 
Not quite dry. 
Holly 
20543 
Hornbeam .... 
.86 
26411 
Not quite dry. 
Laburnum .... 
18000 
Green, or fresh cut. 
Lance-wood .... 
1.01 
25245 
Larch 
.58 
18967 
Lime or Linden . . 
.675 
18309 
Maple 
.7 35 
23947 
Partly cross-grained. 
Oak, English . . . 
20000 
Oak, Hamburgh . . 
.693 
12000 
Oak, Dantzic . . . 
.586 
16500 
Oak, from Bog . . . 
.67 
14500 
Ozier 
18700 
Pear 
.72 
18115 
Pine, St. Petersburg!! . 
10500 
Fresh. 
Pine, St. Petersburgh . 
13000 
Four or five years old. 
Pine, Memel. . . . 
15000 
Pine, American . . . 
14750 
Plane 
.59 
17617 
• 
Plum 
•79 
23700 
Poplar 
.333 
9473 
Satin-wood .... 
1.02 
30000 
Sallow 
18600 
Sycamore 
22900 
Teak 
16800 
Old, and partially decayed. 
Teak, African . . . 
27300 
Walnut 
.572 
19784 
I have observed in a great number of my experiments, that the modulus of 
torsion bears a near relation to the weight of the wood when dry, whatever 
may he the species ; and that for practical purposes we may obtain the deflec- 
tion (o) from the specific gravity ( s ). Thus 
r* l w v 
30000d* s ~ 
