1040 MANGANESE DEPOSITS OF INDIA : DESCRIPTIVE. [ PaRT IV : 
thickness from tliat of a piece of paper to 4 inch and over. In 
some places the manganese oxide forms irregular patches, with remains 
of the charnockite scattered in it. In one place, namely, in a new 
cutting where the Ootacamund railway cuts through the line of hills 
joining Cairn Hill to Elk Hill, I found one of these patches of wad 
over a foot in diameter. The manganese in all these cases must have 
been deri'^/od from the rocks of the charnockite series during their 
alteration into lithomarges. For doubtless the rocks of the series 
contain a small proportion of manganese — probably in the ferro- 
magnesian constituents, such as hypersthene, augite, and garnet — 
although the analyses given in Dr. Holland's Memoir on this series do 
not return this constituent, probably because it was not looked for. 
Amongst the spots where this manganese oxide occurs the following 
may be specified : — 
1. On the path leading along the ridge from Snowdon to 
Dodabetta. 
2. In the new railway cuttings at the western end of Ootacamund 
Lake. 
.3. In the other railway cutting mentioned above. 
4. At several points on the road to Governor's Shola. 
5. By the side of the De Winton Road a little before reaching the 
path to Monte Rosa, as one goes from Sylk's Hotel, and in 
the path leading up from this point through the plantation 
on the hill behind. 
In places there is a small capping of lateritic rock on the lithomarge, 
and in one of these occurrences of laterite I found a little dark brown 
wad. This was near the road-metal quarries close to the 3rd milestone 
on the New Pykara Road. 
Nellore District. 
Dr- Alex. Hunter^ gives the following minerals as having been sent 
from Nellore by Mr. F. N. Crozier to the Madras Exhibition : — ' jet black 
sand containing iron and manganese ' and ' garnet aplome spar'. On 
page 702 aplome garnet from Kaligiri used as emery is mentioned. 
1 Letter No. 347, dated 1st November 1856, to Chief Secretary to Governmont. 
Quoted in Boswell's Nellore District Manual, p. 7, (1873). 
2 Loc. cit. 
