| | | | | | | |Iron, 2.18 |
| | | | | | | | ----- |
| | | | | | | | 100.27 |
| | | | | | | | ------ |
" |Silver precipitate, | | 24| 1| 0| 73| Not | |
| 4 casks | | | | | | det. |Silver, 4.851 | 10
| | | | | | | |Gold, 0.0215|
| | | | | | | |Lead, 19.37 |
| | | | | | | |Zinc, 2.00 |
| | | | | | | |Silver, 1584.7 |
| | | | | | | | ozs. per ton |
| | | | | | | |Gold, 7.0 |
| | | | | | | | ozs. per ton |
" |Purple ore |200| | | | 494| Not |Copper, 0.13% | 11
| | | | | | | det. |Sulphur 0.15% |
------+--------------------+---+---+---+---+----+-------+---------------+----

When the number of samples is small, the Sample Book may be omitted, and
the entries made in the Assay Book as the samples arrive.

_Report-forms._ These should entail as little writing as possible in
making out the report. For general purposes the form given on p. 12 is
useful.

~The quantity of substance~ to be taken for any particular assay depends
largely upon the method of assay adopted. There are, however, some
general considerations which should be remembered, and some devices for
simplifying the calculations which should be discussed.

The smaller the percentage of the substance to be determined, the larger