INDUSTRY AND COMMERCE. 139 
only for porters, whether blocked at any season of year; routes 
likely to be suitable for railways. 
In all cases where practicable, specimens of products should be obtained, 
in order that specialists at home may judge of their industrial or com¬ 
mercial value. 
For those who may have more leisure for observation, some or all of 
the following detailed hints may be useful:— 
Minerals and Metals. —It is not necessary to add much here to what 
has been said under Geology. If the traveller is not himself competent, 
or has no opportunity to test the value of these products, he should bring 
home specimens; this, if possible, should be done in any case. Under 
this section a look-out should be kept for any indication of naphtha, 
asphalt, or mineral oils. From the commercial point of view the impor¬ 
tant points are— 
Quality: To what extent are minerals or metals, as gold, copper, iron, 
phosphates, mixed up with other matter ? What is the yield per ton of 
ore ? In the case of coal, how does it burn, and what is the percentage of 
ash ? Next— 
Quantity: Does the substance occur in sufficient quantity to make it 
worth expenditure of capital and labour? The information must be 
obtained by personal inspection. Finally—- 
Locality : Is the situation of the deposits easily accessible ? How are 
they situated with reference to routes, existing or practicable ? and how 
with reference to ports of embarkation ? Could they be worked with the 
resources available in the country, or would labour and machinery require 
to be introduced ? If worked in the country, is there any neighbouring- 
market for the manufactured products ? What are the native processes 
(if any) of obtaining and working minerals ? 
We must again refer to the section on Geology for further details, and 
the intending traveller would do well to take a few lessons before he 
leaves, so as to be able to recognise the most common and useful minerals, 
and the conditions under which they usually occur; he will thus save 
much time and trouble. 
Vegetable Products. —The directions for observation and collection 
given under the Botanical section should be attended to; and it is 
