428 
Journal of Agricultural Research 
Vol. II, No. 6 
APPLICATION OF RESULTS TO THE CALCULATION OF POROSITY OF 
CROSSTIES 
The following data are excerpted from those given on page 48, in Bul¬ 
letin 126 of the Forest Service, entitled “Experiments in the Preserva¬ 
tive Treatment of Red-Oak and Hard-Maple Cross ties/’ by Francis M. 
Bond: 4 
General records on the individual ties 
RUEPING—RED OAK 
Track No. 
Oven-dry 
weight per 
cubic foot. 
Absorption 
per 
cubic foot. 
Pounds . 
Pounds. 
2 
37 - i 4 
5.00 
3 
36.93 
5-46 
4 
38. 5 ° 
4. 24 
5 
40.30 
5 - 70 
6 
40. 70 
4. 26 
On the basis of these data the portion of the cell cavity occupied by 
creosote is readily computed, since it is known that the density of the 
wood substance of red oak is 1.540; its weight per cubic foot is then 96.06 
pounds. The weight of the creosote used in these tests is 65.5 pounds 
per cubic foot. Table III gives the porosity of the individual crossties 
computed from the foregoing data. 
Table III .—Porosity of red-oak crossties 
Oven-dry 
weight per 
cubic foot. 
Volume of 
Volume of 
Absorption of creosote. 
Percentage 
Track No. 
lignocellulose 
per cubic foot 
of wood. 
cavity per 
cubic foot 
of wood. 
Pounds per 
cubic foot 
of wood. 
Cubic feet 
per cubic 
foot of wood. 
of cell cavity 
occupied by 
creosote. 
2. 
Pounds . 
37 * 
Cubic foot- 
0. 382 
Cubic foot. 
0. 618 
s.oo 
O. 076 
12.3 
3 . 
36.93 
.384 
.616 
5.46 
.088 
14-3 
4 . 
3 8 - 5 ° 
. 401 
• 599 
4.24 
.065 
10. 8 
5 . 
40.30 
. 420 
. 580 
5. 7 ° 
. 087 
* 5 -° 
6. 
40. 70 
.424 
• 576 
4. 26 
. 065 
ii -3 
SUMMARY 
To sum up the results of the investigation: 
The density of the wood substance in different species of trees may, 
for practical purposes, be considered as uniform, with a value of 1.54. 
Since most commercial woods have a density between 0.3 and 0.6, it is 
apparent that the unoccupied space in a block of wood may be from four- 
fifths to two-fifths of its volume. 
