The sun. [volume] (New York [N.Y.]) 1833-1916, 1896-05-10
NOTES ON SCIENCE AND INDUSTRY.

WINS TO convert the brightest OI MS machine
politicians. slowly but surely, Into II reformer.
NOTES ON SCIENCE AND N DUSTRY.
In treating OF the divergence of opinion as
TO the best metal sheathing to lie used on iron
and steel ships. Sir William White, communi-
eating to the English Institution of Naval
Architects, argued that the advocates of cop.
per and zinc. respectively. have each strong
points to urge. Galvanic action between iron and
steel and copper. in which the former would
be the sufferers, had been feared. whereas II
was pointed out that zinc, in its relatively
electrical position to iron and steel. would
practically protect the latter; but under the
test of experience zinc. though protecting the
iron and steel. has failed to it
self ae Il material capable OF maintaining n
clean bottom-the formation Of insoluble salts
on the zinc BY the action Of sea water soon
causes serious roughr ess on the bottom and
tends to fouling. On the whole. therefore. the
conclusion has been arrived at that the extra
cost OF external copper sheath'ng, as com.
pared with zinc, is more than repaid on suisse
0ucnt service by economy Of coal and mainte-
nance. OF speed. What remains is TO find the
ing such copper shoathinE on iron or steel
and to neutrai!ze the tendency to destructive
gaLvanic action upoa the iron Ut steel.
The process brought forward by Heitllng
WI WV ~ W. va it'i''h A''A' ihN w g.
to be absolutely free from silica, is described
In Complies Reudus as very simple. The clay
is thoroughly incorporated with II mixture in
equal parts of ammonia and potassium sui
pilates, In such proportion that three mole
cuics OF ammonium sulphate may be present
to every molecule of alumina. and tho mixture
is made into hollow bricks, which are then
heated in an oven at 27OO to $50 G. At this
temperature both gaseous ammonia and acid
ammonium ~sulrhate are given off. which i'm
mediately reacts with the potash salt present.
acid potassium ~sulphate being formed the
latter, ut the above temperature. combiring
with the alumina of the clay to form alum.
and this is finally extracted from the bricks
by means Of water and freed from iron by re.
rehabilitation, the insolub!e silica remaining
behind being useful in Cemrnls. Granular
Alumina Is prepared BY spreading out the powd-
urea a T Tt4m III { to rn.n w ISEfI q" IS tnsty e %TT Ty FHa
warm, moist. ammorinCal fumes derived from
the, brick oven. As the result of this simple
for ned into alunlinn. retaining the form Of
the original powder, and potassium and am
monium sulphaIes.
Millions OF dollars in gold. says the Mdnufdc-
turrrs' Gazette. are annually taken from rude
heaps OF base-looking quartz by the flowing of
water over huge piles of broken rocks that con-
tain the precious metal; and the water used by
miners in bringing gold from piles or mineral.
bearing quartz Is charged with n simple chem
ical which has the potency to dissolve gold and
hold II In solution the sparkling liquid which
flows over hundreds of tons of quartz, trickles
through the mines. and finds its level, laden
with gold. Ia charged with n deadly poison.
cyanide of potassium, n drug which fcrrets out
the minutcst particles of the yellowish metal
and dlssolves them. bringing the precious bur-
den to the watts for conversion into refined gold
again: The cyanide process is as noiseless and
arr ne IA nNEG nf ~ NEit ftnp. thA
method ia based on tho fact that even a very
weak solution of cyanide Of potassium dis
auro-porassic cyanide and argento- potassic
cyanide. the solution being separated from the
tated in metallic form. Precipitation is ef-
fected. by the use of fine pieces of zinc, so ar
ranged that when the rich waters flow over
them the fine gold clusters in rich deposits over
the zinc. for which II has an affinity the gold
depositing itself In the form OF fine dust on the
plates OF zinc.
Observations upon the preservation of timber
have shown that, the more warm and humid
the atmospheric the more rapidly the wood de-
teriorates, also that timber felled IN winter ia
more durable than that felled IN summer, and
that timber raised In cold climates Is most du.
rable. while the best timber is produced on
meagre soil. When under water. the most last
ing woods are oak, alder. and pine, the least so
being birch. linden. and willow; in the air. tim.
Der is exposed TO the ravages OF insects. this
being the case with zap wood more than the
heart wood woods rich In resin. like the elm
and poplar, are not so much troubled as those
Ike the alder, willow. birch, yoke elm, and red
beech, which have an abundance OF sap and are
rapidly. deteriorated. Timber construction
which Is protected from heat and humidity Is
only endangered by ,y worms, and, on the con;
place Injuries by rotting, which is really the re-
suit ~ microscopic vegetable growths. The
primary cause OF the decay Of wood Is the pres
enCr Of albumlinoid substances in the sap and
inCrnsiing materials, these naturally aftording
lions and their destructive work.
Some Interesting scientific theories, Geologi.
cal and geographical, hRvo been brought to
the attention of the Royal Society of Canada,
by DR.. Robert Bell, and in particular concern
ing what he declares 10 have been Il great pre-
glacial river IN northern Canada, lie points
out the fact OF its having been generally adj
mitted 10y biologists that the continent Of
North America. Immediately before the gla.
clal period, stood Rt IA much higher elevation
than at the present time, amounting 10 per-
haps. between two and three thousand feet,
the inevitable result OF this being TO change
tho river systems from what they now are. and
TO create In the north a gigantic river, drain
ing an area of over one third NJ the entire
North American continent; aud forming a drain
age uasln seven times as large as that OF the
ST. Lawrence, The central portion Of this
great river Dr. BELL assumes 20 have heen In
the middle of what is nov Hudson Bay, az
the north u Canada and the great depth of
The centre Of hudson BAY, and ITS lower part
straits, irto Davis straits, Y Is also main
tanned that the upper half Of the -, lawrence
later geographical period, discharged its wa,
ters northward by. way Of whht Is now Hud'
tut "S one S az the u n Is Gs'S branches saSt Of II tsis sI great
river.