Chap. XL. ] 
VIZAGAPATAM : DEVADA. 
1073 
water, for whicli purpose a couple of pulsometer pumps are employed 
worked by the vertical engines seen in Plate 47. The ore in the bottom 
of the pit cannot be touched until well on into the cold weather when 
the whole of the water has been removed by continuous pumping ; 
after this has been accomplished pumping is still necessary to control 
the constant influx of subterranean water. 
3. Duvvam. 
Part of the main Kodur pit already described is within the limits 
of this village. Between the Kodur pit and the Devada quarries 
shown in Fig. 79, there are several other pits lying in Duvvam limits. As, 
however, they were not being worked, T did not examine them. But 
it was evident from the sides that they had been excavated in similar 
soft rocks to the Kodur pit. 
In the only year, namely, 1899, for which the output figures of 
Duvvam have been separated from those of Kodur, the output was 
571 tons. 
The following figures showing the range of analysis of Duvvam 
ores, now no longer worked, were supplied by Mr. Caplen : — 
Manganese . . . . . . 43 to 48 
Iron 4-5 to 16 
Silica 2 to 4 
4. Devada. 
There !s here a series of shallow excavations showing similar 
kaolin, lithomarge and wad to Kodur, often 
The roclvS. 
with patches of pyrolusite scattered through 
these soft rocks. In places quartz-felspar-rock was seen. In one of the 
pits soft altered rather fine-grained quartz-apatite-spandite-felspar-rock 
(quartz-kodurite) was found, the apatite being light sea-green in. colour 
and up to I inch or more in diameter, while the felspar reacted as 
usual for potassium, and the spandite was pale sherry-coloured. 
A little to the S. W. of this pit I was shown a spot from which 
some eight years previously some hundred- 
weights of large crystals of apatite had been 
obtained. The excavation then made had become silted up with 
clay, but round the edges I found abundance of the soft rather 
