MINOR VEGETABLE PRODUCTS AND THEIR SOURCES. 189 
when it turns to a beautiful dark color. Like other varnishes derived 
from the same natural order, it is very caustic and apt to cause erysipe- 
latous swellings, if applied to the skin. The wood of this tree is excess- 
ively hard and heavy, and is called the lignum-vite of Pegu. Anchors 
for boats are made of it, and it is employed for all purposes where great 
strength and durability are required. 
Dipterocarpus trinervis and D. levis (Dipterocarpee) are Hast Indian 
trees that furnish thin liquid balsams used medicinally, for burning in 
torches, and for painting vessels of various kinds. The resinous fluid is 
collected by cutting a deep notch in the trunk of the tree near the 
ground, where a fire is kept until the wood is charred, when the liquid 
begins to ooze out. Itis much used as a varnish for window-frames, 
doors, &c., and has been found a good substitute for balsam of copaiba, 
which it greatly resembles. By the application of heat it becomes con- 
centrated aud semi-solid. Mixed with dammar resin it has been found 
valuable in preserving timber from the attacks of insects and worms. 
Shorea robusta, (Dipteracece,) a fine timber tree of the Himalaya mount- 
ains, furnishes a resin which is known as a variety of dammar, and is 
adapted to the same uses. An oil is likewise obtained from its seeds. 
The wood of this tree, as also that of 9. selanica, is known as Saul- 
wood, which is close-grained, strong, and durable, and is employed for 
ship-building and engineering purposes, where great strength and 
toughness are requisite. It is considered stronger, as it is heavier, than 
the famous teak wood of India. 
Opopanax gunis the milky juice of Opopanax Chironium, ( Umbellifere,) 
a plant closely resembling the parsnip, native of the south of Europe. 
The milky juice dries into a gum resin, having properties very similar to 
those possessed by ammoniacum, 
Mesquite gum.—This is yielded by Prosopis glandulosa, (Mimosece, Leg- 
uminose,) the mesquite tree of Texas. This gum closely resembles gum 
arabic, and, as the tree is allied to the true gum-producing family, it 
may be found worthy of attention for its gum. 
ign aloes.—The tree called calambac by the ancients, and which fur- 
nished the aloes alluded to in the Bible, where it is said “All thy garments 
smell of myrrh, aloes, and cassia,” is supposed by some to have been 
the eaglewood, Aloexylon Agallochum, (Leqguminose,) a lofty, upright-grow- 
ing tree, native of the mountains of Cochin China and the Moluceas. It 
yields a perfume which is the most esteemed by Oriental nations. The 
oleaginous particles stagnate and concrete into resin in the inner part of 
the trunk and branches, by which the natural appearance of the wood 
is altered, becoming of a dark color, and acquiring a fragrant smell. At 
length the tree dies, and when split open the resinous part is removed. 
it contains little else than the camphoraceous matter, and receives the 
name of aloes from its bitter taste. The wood of this tree is very valua- 
ble. Some of the most precious jewels of East India manufacture are set 
in it, and it sells at the rate of $3,000 per ton. This tree is supposed to 
be the plant alluded to in theScriptures, Numbers xxiv, 6: “As the val- 
leys are they spread forth, as gardens by the rivers’ side, as the trees of 
lign-aloes which the Lord hath planted, and as cedar trees beside the 
waters.” Owing to the imperfect knowledge of botany possessed by the 
ancients, and the meager descriptions they have left, there has been a 
difficulty in accurately defining the tree which produces this fragrant 
substance; hence the aloe wood of India has also been mentioued as 
the source of this resinous perfume. This is the Aquilavria Agallocha, 
(Aquilariacee,) a broad-spreading tree, containing a highly odoriferous ' 
resin, and an essential oil which is also held in great esteem. The 
