PART 3.] 
Hockstetter, Geology of Nicobars. 
69 
may be observed along the coast. Until the interior of these islands has been examined, the 
question regarding coal on the Nicobars cannot be answered in any other way than it was 
by the first expedition. 
Equally unfavorable must he the opinion regarding the occurrence of ores or other useful 
minerals. Nothing of the kind has yet been foiina on the Nicobars. Gold and useful 
minerals are partially rich on islands and along coasts which, viewed geologically, belong to 
the same area of elevation as the Nicobars, as I have already pointed out. The natives 
who long ago observed those fragments of coal, who use glass pearls, silver fragments, &o., 
as ornaments, who know the plants and animals of their islands pretty well, and who 
have for all more common phenomena, for all useful products of the animal and vegetable 
kingdom special names, these inhabitants have as yet found among the rocks of their islands 
nothing that they would be able to make use of for ornament or other useful purposes. The 
only traces of ore which I found were those of ivon pyrites and copper pyrites, finely 
disseminated through dioritic and serpentine-like rocks. The possibility of the occurrence of 
copper ores in the eruptive formation cannot be denied; however, no discovery has as yet 
been made which would indicate it. On the other hand, the islands are rich in useful building 
materials. The sandstones of the southern island must give excellent working stones; the 
plastic clays of the northern islands could no doubt be equally well worked into bricks or into 
pottery; the natives of Chowry make large pots of it. Finally lime is offered by the coral 
reefs in inexhaustible quantity along the coasts of all the islands. 
III .—The soil and Us vegetation. 
[ Only brief extracts of this section are given. J 
Dr. Hochstetter states that vegetation in its original state always indicates the character 
of the soil, provided the atmospheric conditions are the same. This is, however, on the 
Nicobars, highly the case. ' Neither the difference in the latitude from the most northern to 
the most southern islands (2f degrees), nor the difference of the absolute elevation (the 
highest hills on Great Nicobar only attain about 2,000 feet above the sea), is large enough 
to produce on the single islands, or parts of them, such a difference in the climatal conditions, 
that on it alone an altered character of vegetation should depend. Ilocks, soil and vegetation 
are, therefore, on the Nicobars in such a degree related to each other, that the areas marked 
on a map as indicating various rocks would almost coincide with those indicating the varieties 
of vegetation. Unfortunately the sketching out of such maps for the larger inaccessible 
islands is impossible; to indicate it I can only attempt a representation of the small island 
Milu (PI. 4, Fig 5.) and the north-western bay of Little Nicobar.’ 
‘ The results of these observations may he seen in the following tabular view :— 
Geological character of the underlying 
rock. 
Character of soil. 
Respective character of vege¬ 
tation. 
1. Salt and brackish swamp, damp 
marine alluvium. 
Swampy groom'll not capable of cultivation. 
Mangrove-forest. 
2. Coral conglomerate and coral sand, 
dry marine alluvium. 
Fertile calcareous soil; principal cons¬ 
tituents, carbonate and phosphate of 
lime. 
Cocoa-palm forest. 
3. Coral conglomerate and coral sand 
beside dry freshwater alluvium. 
Fertile calcareous sandy soil. 
Large forest trees. 
4. Freshwater swamp and damp fresh¬ 
water alluvium. 
Swampy ground, capable of being culti¬ 
vated. 
Pandanus forest. 
6. Plastic clay, magnesian clay, marls 
and partially serpentine, 
* 
Not fertile clayey soil; principal consti¬ 
tuents, silicate of alumina and silicate 
of magnesia. 
Grassy plains. 
6, Sandstone, slate, gabbro, dry river 
alluvium. 
Loose clayey, sandy soil, rich in alkalies 
and lime, very fertile. 
Jungle (the true primeval 
forest). 
