The Pioche weekly record. [volume] (Pioche, Nev.) 1877-1900, 1882-08-19
HINTS TO PROSECUTORS.

Az the last meeting OF the san fran-
cisco Mioroscopical Society, Mr.. H. G.
Hanks, State slineragolist read paper
"On the use of the Direct Vision Spec
troscepe in Prospecting for Boracic Acid
and Borax:"
The Mining and Scientific Press says
he called attention to the Importance OF
this useful and rare mineral stating that
all the borax known on the Pacific coast
is found in deposits, the exhaustion of
which is only question of time, and it
is important that others should be found
"In prospecting the deserts of Nevada
and California" said Mr. Hicks, there
are no facilities for chemical operations,
and the prospectors, generally poor, can
but i'll afford to send their samples to
San Francisco or pay the cost of chemical
analysis. These considerations have no
doubt retarded the developments of the
borax interests in the State.
All these difficulties may be overcome
by the use of the spectroscope This
convenient instrument, which | am in
debted to Mr.. Charles w. Banks, of this
society, for this opportunity of showing
you this evening, is only three and a half
inches long, and, with its case, may be
carried in the vest pocket. Yet with it,
bottle of strong sulphuric acid, one of
alcohol, and small evaporating dish,
the prospector, although unskilled in
chemical handicraft, may detect with un-
erring certainty the presence or other
wise of boracic acid or any of its salts in
the deposits he may find
The operation is simple, and once seen,
is easily understood. The salt is placed
in the evaporating dish, and few drops
of sulphuric acid added A brisk efferva-
tion generally takes place. The contents
of the dish must be stirred, which may
be done with small stick Or anything
convenient at hand. Alcohol is then
poured in, in small quantity, and ignited.
All that is then required to determine
the presence of borax or boracic acid is
to look at the flame through the spectre
scope. Two distinct and beautifully
green bands will be seen if boracic acic
is present.
If free boracic acid is obtained in ths
sample, the green bands may be produced
without the introduction of sulphur,
acid. 1t is best, however, to always us'
the acid, which decomposes the salt con
tanning the weaker boracic acid, and t.
make secondary test to prove the bo
racic acid to be free or otherwise. whel
boracic acid is suspected in steam issuing
from hot springs, it is only necessary t
eondense portion of the steam. Th
resulting water is evaporated nearly t
dryness at very gentle heat; alcohol
then added and the flame examined a
before. This test shows the presence {
boracic acid in the waters of Mono Lake
and IN the eruptive mud from the mu
volcanoes of the Colorado desert, Sa
Diego county.
The only weak point in this determin:
tion lies in the extreme delicacy. In e,
perienced hands it might lead to the hoI
that the sample was rich when borac
acid was present only in small quantitie
but little experience will correct thi
for it will be seen when the quantity
small the bands are faint, and come an
go in an intermittent manner; while,
the quantity is large, the bands are di
tinct and well defined, and the color
clear green As with the sodium ban
the intensity Of the color is an index
quantity--all of which may be learned
experience. In making this determin
tion all bands of other substances preser
as lithium, potassium, ETC., must be d
regarded.