New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1873-03-10
DEEP PLACER MINING.
ircrrpp nv PROF r. svLLIMAN.

Another OF the series Vi Tree ieCtuoo az '"0
rooper Union wss aelirczee Saturday evening by
PRO-, slnman Of Yale Colo 20, on Deep Placer Mining
a. Cahtornia" An mv ense audience gathered, aud
yearly All remained the close Of the lecture which
eonsumed about two hurs although 1t was delivered In
an unusually rapie conversational manner The Illus
sra,,ous were pref and even continuous embracing
snes in CallfOTr mining regions both In later ana
earlier years, and diagrams of the machines ana pro
uesses employed then and now 10 beginning his iectare
Prof. sinimsA said;
LADIES kxp GENTLEMEN: The birth Of a continent is
subject interest in the history OF ths woru tna'
YOU wepa hardly expect me to enter upon that chapei
In any eetal, since the Genesis OF inc continent VI
NORTH America alone were to exhibit II to you even
An it, Nriefest outlines would require 30 rapid turning
of the pages OF that great OF Nature upon whch
t,r records are inscribed that would be weary DC
fore fairly entering upon our subject Hls 10 10 oi"
in mind that great outline features OF TINS Con'u
Of ours as of all the other great continents VI ~
world were laid definitely far back IN geoiogic his
,v and that il ia the best opinion Of those who are
heat informed on all these subjects In our u"F' '"'
where the continents DOW are they nave ever oee"' w
that the old idea in which some OF us III tne carry "'
of geology were reared, that where oceaus no" are
there were formerly continents, no longer tenaoe
oa but that the substantial truth seems 10 lie I'D inc
a,roction have indicated, that where the Continent
now Ia essentially in main outline features IL mas
ever been during all the past periods OF the WORRIES HIS
tory.
lecturer then spoke OF inc NestSih NVun'J "N"e
the line OF the Pacific railroad beyond the Mississippi
n said be 10 be one vast oceanic plain along
the f the river Platte and up those slopes OF the
Rocky Mountains which, In the days OF our ignorance
and Youthful enthusiasm in these matters we consldereu
20 be but which we hnd IL the race OF
actual fact be just insurmounabe as any other
dead level plain, because for 800 miles or more the
Grade Is not more than Is feet TO the mile,
M thai the eve fails 70 detect the fact that is anything
else than dead level 1t here that the subsidies
of seseQ per mile for the Union Pacific Railroad were
paid Cheyenne, where II was decided that the
Rock Mountains proper began. Although from that
point 10 the Black Hills per mile were paid as the
subsidy the country still appears TO the eye OF the trav
.ler @ level plain. No who looks for the Rocky
Mountains to-day can understand why so much should
be paid when he gets TO the foot OF the BLACK HIS
that should be paid because il has no greater o
neues 20 encounter than that encountered every DAY
in an ordinary passage along railways in the Eastern
States speak this only 10 show how easy 1t is Tor
men 90 magnify difficulties and TO overestimate them
enormously when they judge them only in the hght OF
their ignorance want of familiarity with the facts IL
81 fortunate, however that the gentlemen VINO con-
srueted Union Pacific Railroad did not pass through
Denver and Berhoud Pass. which the original de-
sign for II they had railroad would not have been
done TO- lay and the whole avails Of the Credit Mober
would have been inadequate TO the expense Applause
and laughterl
OLD METHODS OF GOLD WASHING.
ton Of ancient geological condition of California as
compared with that which exists, showing how the
gold region OF the Sierra Nevada reached and re-
marking all cahons in the country were formed ages
ago by action OF running water which left the heavy
gold in small PARTICLES behind in the creyices OF the rock
and the beds Of streams which were able TO get
&c by simple process as digging up the gravel ana
washing 1t out In portions Of California there
were areas where the deep lying gravels had been
washed away completely that all the gold was left be-
hind and much $4,000 had fallen TO the lot OF
single prospector in small area OF perhaps is by Is
feet But those things only historic the days
are past when men can pick up gold the surface OF
California and the primitive plan OF pros
pectine" with the pan was long ago
superseded by moro efficient methods
When water could be had in the Spanish Dry Dig
gings then the process OF wtnnowinR was employedi
that is the dust was tossed blanket some loosely
spun material where the gold could be separated as In
sieve The step in the application OF mechanical
ski early days Of California, was the introduction
of the rocker cradle-nOt the baby however Laugh
teri for washing gold This is carried on even now in
California on a small scale, but 1t is used
almost entirely by Cinnamon. The next step
in advance was the introduction Of the "Long
Tom" an apparatus designed to permit the con-
tinuous flow of stream Of water through long trough
placed at suitable incline. and provided at tsower ex-
trety with plate obquely against whchthe
mercury contained bottom Of the apparatus rested
The OF this form OF apparatus very great
"a compared with anything which had been previously
employed but was very inferior to the methods of
slueng by the hydraulic which have since come to re-
place all the older methods OF gold-washing
The lecturer then illustrated upon the screen the
methods Of river mining by Of which the rich de-
posits in the bottom Of the streams were reached
during the dry months of Summer, the whole
water OF the stream beng carried III an art-
fetal fiume constructed Of planks, on one side
of the valley, while the power OfEthe running
water was made available pumping from the former
bed of the stream laid bare the water accumulated
in pitt the gOdbeariDg gravels being removed by
handbarrows and separately treated by the process OF
sluicing THIS method is still practced large scale
by the frugal industrious Chinese, but has been
abandoned almost completely by the Americans. But
che most important step which has been made was
An the introduction Of the hydraulic and there
an apparatus known as the "knuckejoint nozzle from
Winch stream Of water six inches in diameter is pro-
,cted against face Of the bank in almost unbroken
column with force something like the discharge OF
ordnance.
DEAD RIVERS SEALED WITH BAsALT.
Before speaking OF this important mode Of gold
washing the lecturer explained very fully the nature
and extent Of those great deposits Of aurerous gravel
which seem on so grand scale. He referred then to
the remarkable phenomena OF the Table Mountains,
which constitute prominent and most characteristic
feature Of the gold region at numerous eS points
from 'Otoshe 49,, uO ~ The Psiisades of the
Hudson f%s being Ike them, of volcanic origin.
They are in fact portions Of the lava streams poured out
extensively during the great epoch OF volcanic &C
tiyty which closed the Of the ancient Tavels III
that period OF the worlds history called by BIOLOGISTS
the Plei0cene The speaker explained from diagrams
upon how these lava streams filed the val
leys of ancient long before the alterations Of the
surface TO subsequent denudauon, which has had
The effect leaving this solid basat unchanged almost
rompetely while the surface OF the country surround
ing has been down from 200 TO 1900 feet by
fhe valleys Of existing The sagacity Of the early
explorers OF the gold region OF California detected the
Tr,ie nature Of these remarkable dead rivers
Of tbe Puoeene time long before any, hint
had been given by the scientific world as
10 their nature. The adventurous ana hardy
.S,rs undertook exploration Of these streams.
hard Laaal hu