162 
Records of the Geological Surrey of India. 
[vol. VII. 
doing away with the necessity of having specially educated workmen; and another great 
advantage lies in the fact that the bricks can be handled almost immediately after leaving the 
press. 
Dry pitch is not a constant product. According as the distillation has been pushed too 
far. or the contrary, its density varies between 1’286 and 1’275. If the evaporation is 
carried on to dryness, a product is obtained deficient in agglutinating properties, and it is 
found necessary to add fluid pitch, tar or some heavy oils. The following is an analysis of 
dry pitch of I'28 density ;— 
Carbon 
Hydrogen 
Oxygen 
Ash 
75*32 
8*19 
16-00 
*43 
100*00 
Tlie above extracts will suffice to show that M. ITabets is an advocate for dry pitch as an 
agglutinating material; and the experience gained in Belgium and the north of France 
certainly points to it as best adapted for the purpose. But he points out that this process 
has not been adopted in the south of France, owing to the heat of summer making it 
difficult to reduce the dry pitch to the state of powder; and until this difficulty is sur¬ 
mounted, the same objection would hold with even greater force for India. In the southern 
provinces of France the soft-pitch process prevails, smoke-consumers being adapted to the 
furnaces to obviate the evil effects of the mass of volatile products; the same system could 
probably bo applied to the case of India. It was no doubt considerations of this nature 
that led Mr. Danvers in his book on coal to elect in favor of the starchy cements for India ; 
and at present the choice seems to lie between these and the soft-pitch process. 
M. Habets makes little or no specific mention of the other substances enumerated in the 
3rd, 4th, and 5th sections of his list. We may presume that no practical result was obtained 
from them. His essay is most valuable for the detailed descriptions and figures of the 
different processes of manufacture. 
Some attempts have been made to adapt farinaceous agglutinants to the semi-bituminous 
waste of our collieries in the Raniganj field ; and considered as mere experiments they were 
successful, but commercially they were failures, Rico and Indian.com were both tried, and 
they formed good cements, but they constituted a very heavy item in the cost of production. 
I think the time has scarcely arrived for the manufacture of artificial fuel to be a suc¬ 
cessful industry in the Raniganj field while whole coal can be procured at its present or 
even at a considerably enhanced price; but with regard to the Darjiling coals (which can 
only be extracted as dust), and to a certain extent those of the Wardha valley, the only 
course left for utilising them in the absence of the possibility of converting them into coke is 
to make them into brick-coal.* 
Some trials have recently been made in the Central Provinces to consolidate the coal of 
the Warora colliery—which is of a very friable nature—by moans of rice and gum, &e. 
The proportions of the substances used were— 
... 112 lbs. 
1 lb. 
Jib. 
£ gallon. 
... ... 4 grains. 
4 
* My colleague, Mr. Mallet, was the first to sufrgest that the Darjiling- coal, in order to be rendered available 
ought to be made into patent-fuel. 
Kice 
Guru 
Water 
Nitrate of soda 
Potash ... 
