FIREWOOD LT 
TABLE XXII.—Analyses and calorific determinations of air-dried bark. 
[The numbers and common names are those given by Cox in the original table. The 
scientific names have been inserted by Mr. E. E. Schneider, wood expert of the Bureau 
of Forestry, after a recent examination of specimens of the wood used by Cox.] 










value of Available 
| ne eine pone value of 
No. | Common and scientific names. | a Ash. enlge areas pase ol ee 
ries. value. (water malta, 
eae Gvater 
calories. tash). 
| | Per cent. | Per cent. Calories. Calories. | 
3 | Pototan (Brugwiera conjugata) | 138.90 6. 72 3, 983 3, 668 4, 863 4,568 | 
4! Bacauan tubig (Rhizophora 
mucronata) ....----.--------- 10. 23 10.37 3,971 3, 664 4, 884 4,575 | 
4, 054 3, 708 5, 124 4.791 
6 | Bacauan (Bruguiera sp.) --_--- 15. 67 8.19 1 4,034 3, 692 5, 099 4,771 
7 | Catutan (Brugwiera sp.) --_--- 16.27 4.60 4, 037 3,710 4, 920 4, 624 
8 | Tabigue (Xylocarpus moluc- 
CONSTS) eee ee ALE 16.21 7.98 3, 848 3. 488 4, 857 4,510 
9 | Bacauan (Bruguwiera sp.)------ 15. 70 8.17 3,891 8, 565 4, 903 4,594 
10 | Tambu-tambu (Xylocarpus 
moluccensis) .....------------ 15.74 8.39 3, 841 3, 536 4, 853 4,571 


b See footnote ‘‘a’’ of Table XXI. 
Concerning the relative value of mangrove-swamp woods and 
imported coal we may quote the following from Cox: 
The available heating value of any well-seasoned wood is about 3,680 
calories, and the specific gravity of well-seasoned mangrove wood (Rhizo- 
phoraceae) is about 0.9. From the latter value the weight of a solid 
cubic meter of meter lengths is about 900 kilograms and of a solid cord 
(8 by 4 by 4 English feet) is about 3,260 kilograms. In some parts of 
the Philippine Archipelago 2 cubic meters (2 by 1 by 1 meters) are called 
a talacsan. Since there are generally 35 per cent of voids, or interstices, 
in wood of a meter or more in length, one actually obtains about 585 
kilograms and 2,120 kilograms of this wood in a cubic meter and in a 
cord, respectively. The available calorific (fuel or heating) value of green 
wood is less than that of dry wood by an amount not only proportional to 
the decreased wood fiber per unit weight, but also by the amount of heat 
necessary to evaporate and be carried away by the excess moisture, and 
that of green mangrove wood containing 38 per. cent water is about 2,420 
calories. * * * A commercial concern found that a cord of green man- 
grove wood contained about 18 per cent more water than well-seasoned 
wood weighing 2,550 kilograms, which checks with these numbers. The 
available heating value of an average imported coal (Tagawa) is approxi- 
mately 6,500 calories. From the above numbers it may be computed that, in 
general, a ton of this coal is theoretically equivalent to 3 cubic meters 
or 0.83 cord of air-dry Philippine mangrove wood and to 3.24 cubic meters 
or 0.89 cord of green mangrove wood containing 38 per cent moisture. 
In the latter case 42 per cent extra weight will have to be handled. How- 
ever, various consumers report the use in actual practice of one and 
one-third or more cords of wood in lieu of 1 ton of coal. 
