Richmond dispatch. [volume] (Richmond, Va.) 1884-1903, 1898-12-01
Notes on Science an Industry.


Near Salmon City, Idaho, gold dredg-
! ing plant Of remarkable proportions IS q
process Of building by the II. J. Reling
| Company, of Chicago. This notable plane
| is Of the New Zealand type, with all the
| heavy parts of annealed steel and with
| a daily capacity, estimated at 1900 yards.
| The boat was fiOated some time since.
and the vast machinery exhibited the
most satisfactory efficiency for the pur-
pose the final tests to be made in the
near future. This plant has been worked
heretofore by hydraulcking, at such times
as the water supply permitted, and 1t
produces what has the reputation of
being the purest article Of gold found IN
Idaho, being worth nearly $40 per ounce
as it comes from the ground. Moreover,
the pay-streak of this remarkable locality
is 200 to 800 feet wide, II to 20 feet deep,
and averages 60 cents per cubic yard.
A remarkable discovery Of sodium car
Donate is announced as having lately been
made in Sonora, Mexico, two miles inland
from Adair Bay, an indentation from the
Gulf OF California, 100 miles south Of the
Colorado river. The deposit covers an
area of about seventy acres in extent,
In the centre of which are several flowing
springs, the water being strongly i'm
spread over the surrounding area, and
evaporation has formed a crust Of the
crystalliZed salts / to feet in thickness,
beneath which is a foot or Is inches OF
water: as this crust which is the product,
is excavated and taken away, the water
from below quickly fills its place, and
very shortly, by evaporation, IT Is COM
pletely renewed. making the deposit prac-
tically inexhaustible, it being estimated
that there are fully 10000 tons of the
material available in this locality.
And now an enthusiastic French en-
gineer NJ. Paul Issartier, proposes tun-
mel TO the centre OF Mont Blanc, ascending
from this vertically a mile and half 70
the summit, such a tunnel to be nearly
10 900 feet long, terminating at 1890 feet
above sea level, after a rise OF 600 feet
in its length, and from this vertical
shaft. 10 by Is feet in size. TO the summit,
some 500 feet above. To accomplish
this the excavating would be done from
below; a strong. two-storied steel cham
Der would be raised on steel racks at the
corners of the shaft, the upper floor car
rying the compassionate drills and the
lower one be caught on steel gratings, |
passed TO the bottom OF a
shaft in a 12-inch tube, and then washed |
away in a stream from centrifugal pumps. |
Before making a blast the chamber would |
bs rolled to the other side of the shaft. |
As stated in th- scientific American |
lately Professor 4. Cray has been do |
voting a considerable part Of his time to !
the circumstances when sDe-
cially affect the con1uctivity and spe-
cihc capacity OF glass. From manufac- |
turers in London and Jena various speci- |
mems OF glass were obtained for this pur-
pose. these being all richer in lead and |
freer from soda than glasses formerly I
available Specimens OF the material used |
for thermometers, and a barium crown !
glass. were also subjected 10 the differ
emit tests IL was sought 10 ascertain
whether by increasing the lead oxide and
the amount OF soda, the con-
ductivity would 20 on diminishing. The
resistance was taken after five minutes !
The Jena glass showed
OF dielectric polarization. and
Powelps glass did the same; the barium
glass showed hardly any. but II had a
very high resistance, and behaved Ike
cad and lime glasses. The Jena glass had
ow resistance. from It's high percentage
II soda and complex composition.
There has just been brought forward a
portable electric safety lamp for use in
pecial cases when an open flame, or
wen one safeguarded. as In the miners
amp, would prove dangerous. The COM
,ination consists OF dry battery ar