550 
MANGANESE DEPOSITS OF INDIA : MIXING. [PaHT III : 
would, however, be prohibitive in cost and unnecessary, were the 
' country ' hard and sound. On the other hand, the soundness of the 
o-round would reduce the cost of true mining on account of the smaller 
cost of timbering required, and might make mining cheaper than 
quarrying. 
The presence of water m a deposit is also of great importance. One 
of the reasons why it is possible to work to 
The presence of water. gj.gg^pj, (Jepths opencast on a deposit situated on a 
hill, than on a deposit the top of which is only at plains level, is that the 
former deposits are usually comparatively dry, and if not they can be 
easilv rendered so by the construction of drainage adits driven into 
the side of the hill. Pumping, when necessary, may be a serious item 
in the total costs of mining. 
5. Tn cases where it is doubtful whether to quarry or mine a deposit 
the relative costs of the tools and plant required 
and°plant^ ^™ °° " cases, and the cost of the timbering 
that may be required in case underground mining 
is resorted to, have to be considered. 
6. When labour is very cheap it may often be advisable to work 
a deposit in a simpler way and with less labour- 
Cost of a our. saving apparatus than would be desirable in the 
case of dear labour. India is a country of cheap labour. But it must 
be remembered that besides the cheapness of labour, as measured by the 
wages per head paid, the efficiency and abundance of the labour has to be 
considered. Though the amount of ore or coal excavated per man 
per day is considerably less in India than with European labour in colder 
climes, vet the greater expense of the white labour probably overbalances 
the extra efficiency. [In coal mining it is probable that no country 
works more cheaply than India.] Further, if a supply of labour 
cannot be obtained sufficient to keep a mine in full swing, as often 
happens in some of the manganese-mining districts of India, then in 
spite of the relative cheapness of such labour as is obtainable it may 
still be desirable to make use of as much labour-saving apparatus as 
possible. In considering the respective merits of quarrying and mining 
in the case of a deposit extending to such a depth that it might be 
treated in either wav, it has to be remembered that for underground 
work a greater proportion of skilled labour is necessary than for opencast 
work. It then usually happens that the labour for underground work 
has to be trained, or to be imported from elsewhere at a higher rate 
than would obtain for local labour employed for opencast work. 
