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Head-Quarters, Calculla. The Director.
R. D. Oldham, A.R.S.M., 1st Grade Deputy Super
intendent. T. H. HOLLAND, A.R.C.S., Assistant Superintend
ent. Mr. Oldham is engaged in the preparation of the Manual of the Geology of India : Mr. Holland is in charge of the Museum and Laboratory, but will be deputed during part of the field season for the collection of a series of specimens and notes illustrative of iron in India, especially in connection with the requirements of the Imperial Colonial and Indian Institute. Sub-Assistant Kishen Singh will accompany Mr. Holland.
The Director was on tour from the 3rd of September to the 23rd of October at Madras, in the Salem and Kurnool Districts, at Hyderabad, Ahmedabad, Ajmere, the Mohpani Colliery, and in the Punna State. At Madras, owing to the impending retirement of Mr. Foote, a scheme was arranged with Dr. Warth, at present transferred from the Survey as Officiating Superintendent of the Government Central Museum, to carry on geological research during the collecting tours organized in that Institution. At Salem, the revived question of the leasing and development of the enormous iron-ore tracts in that district, which has now been dormant for over a quarter of a century, principally through the paucity of wood-fuel and burdensome transport rates, is to be assisted by Mr. Holland's iron enquiry during the next field season. It having been reported by the district officials that the steatite mines of Betumcherla, in the Kurnool District, did not appear to be capable of yielding the small quantity of fine stone (locally called “bulpum") of the block-dimensions asked for by the manufacturers of gas burners in London, a visit was paid to these mines. The thicknesses of the beds are, as a rule, too small to allow of 6-inch cubes, though there is some cause for assuming that the limit of cube laid down may have been given at random, considering the small size of the articles manufactured; but there is no doubt that plenty of the stone, thin as it is, is obtainable under a better method of mining than the irregular grubbing excavation pursued by the local miners. At Ahmedabad, Mr. H. E. M. James, then Commissioner of the Northern Division, reopened the question last year of a possible improvement of the water-supply of the district by resorting to artesian boring ; but opportunity could not be arranged until the present tour for taking it up further than had been done in the discussion by the previous Director (Mr. Medlicott) in 1885, that is, by personal inspection of the country. The conditions of uncertainty continue as stated by Mr. Medlicott, but there are grounds for expecting a rather larger supply of deep percolating sub-alluvial water than he calculated on, though there is no knowing whether it will be sweet, or that it will rise to a sufficient height in the wells. It is after all little more than a matter of chance, and exceedingly much a matter of cost; but an estimate is being made of the probable amount of the latter, with a view to deciding whether an arrangement can be made for an experimental boring in the neighbourhood of Viramgaum, where it is understood that the greatest difficulty is apprehended in keeping the present ordinary wells from becoming too brackish. At Ajmere, a similar request as to artesian possibilities had been received from Captain de Lassöe, the District Magistrate ; but an inspection showed that there is no hope in that direction, there being no alluvial tracts of any extent, while the stratigraphy of the proper rock-series is en.
tirely against it. At the Mohpani Colliery, the deep boring, for which certain rebatements in royalty had been allowed by the Central Provinces Government, is now being shoved on with renewed vigour, the Narbudda Coal and Iron Company having imported an American portable steam-boring machine, which so far, but only after some slight modification of the handling gear, and training of the men, seems to be running most satisfactorily—a result which is most cheering after the disappointing experiences reported concerning the working of the Survey machine at the late Daltonganj coal-field boring exploitation. Au Punna, H. H. the Maharajah was advised as to the extent of the mineral resources of his State.
Mr. R. Bruce Foote, Senior Superintendent of the Survey, retired from the service on the 30th September, after a long and distinguished career of over thirty-three years, two of which were on extension of service. It is, however, most gratifying to know that his geological work in India does not close thus, his services having been secured by the Baroda State for the closer determination of its mineral re. sources.
Mr. W. B. Dallas Edwards, Associate of the Royal College of Science, London, joined the Department on the 20th October, as Assistant Superintendent, 3rd Grade.
List of Reports and Papers sent in to Office for publication or record
during August, September, and October 1891.
Report on the Work done in the Laboratory of the Geological Survey of
India during the months of August, September, and October 1891,
by Thomas H. HOLLAND, A.R.C.S., F.G.S, Geological Survey of • Indin.
In addition to the results obtained in the examination of the rocks from the Salt Range, published as a separate note in this part of the Records, a number of assays
and determinations of specimens have been made of ores, oils, and other substances. A list of these is given below:
1. Brines from the Sambhar Lake, Rajputana. The following preliminary report embodies the results of my examination of four samples of brine and one sample of dry residue collected in March last from the Sambhar Lake, and forwarded by the Assistant Commissioner of the North India Salt Revenue, Sambhar. It has been decided that further samples be collected after the rains, to be subjected also to chemical examination.
No, 1.-“Brine taken from new channel between Kyar No. 1 and Station, 10-15 A.M., 21st March 1891" (iabel).
The brine was pink in colour and slightly turbid, with a disagreeable odour. The specific gravity at 87° F. was 1.231. The liquid boiled at a temperature of 107.5° Cent., and gave a decidedly alkaline reaction with litmus.
For the purposes of chemical analysis I have employed the methods and have taken advantage of the results obtained by Professor Ditimar in his elaborate examination of the samples of sea-water collected on the “Challenger” expedition. The toial bases were estimated as sulphates, in which soda was determined by deducting the sum of the remaining sulphates, these latter in each case making a very small quantity. In the chlorine-estimation no attempt has been made to separate iodine or bromine; the result therefore is total hilogen in each case. These remarks apply equally to the remaining samples of brine whose analyses are stated below.
The following is the composition of No. 1:
"The temperature at which this determination has been made is about an average tempera. ture for liquids in Calcutta during about eight months in the year; and the rates at which solutions expand on increase of temperature being variable, it is impossible to make any safe correction to 60°F. On account also of the increase of the co-efficient of expansion of liquids at higher temperatures, determination of the specific gravities of liquids above 60° F. introduces a serious source of error.
Combining these acids and bases we obtain in 100 parts of brine-
· · · · 1084
Calcic sulphate (CaSO4) . . . . 15*18
No. 2.-" Brine taken from channels between Kyars Nos. 1 and 6. Time, 10 A.M.; 21st March, 1891" (label).
This specimen was tinged of a smoky colour, was turbid and with slight sedi. ment at the bottom of the bottle. The same disagreeable smell referred to in No. i characterized this sample.
Specific gravity : 1.229 at 87° Fahr.
Water : : : : : : : : : : : 28 755