Wheeling register. [volume] (Wheeling, W. Va.) 1878-1935, 1896-03-27

Brings Unexpected Dangers.
Landing Through the Surf on an
Unknown Shore Great Exact
ness with Which the COinputa-
tions Must be Made.
Life and limb are frequently endan-
gered by Uncle Sans mapmakers
aboard the good ship Thetis, which was
recently in the harbor Of San Diego,
Cali. for stores. and to give the crew a
chance TO enjoy the holidays.
The Thetis is surveying the coast or
Lower California. securing information
as TO the depth of the waters, the char
aCter of the oceans bottom, the exact
length of the shore line, the height OF
every peak Of prominence that is really
observable from the ocean, the yarl-
alton of the compass all along the
coast. the dip of the magnetic needle at
frequent intervals, the latitude ana
I longitude of the mountain peaks, and
the exact position of all rocks and
shoals
I'm addition to being expert seamen.
IUN UNllELr Oh NlAAo hNcoNi tAAN N-Nlf
scientists. They have 10 observe the
stars with the utmost accuracy in de-
termining the time of hundreds OF
points 70 within a possible error OF a
few hundredths OF a second. Thirteen
thermometers are used in keeping
record Of the time
These are a few of the duties devOlv-
ing upon these men in addition to the
duty of navigating the vessel and fol-
lowing the routine necessary aboard
man-Of-war.
The securing of surroundings is an in
teresting part of the work. From TWO
signal points on shore the exact posi-
ton Of the ship is determined by trian-
guiatiOn
On a line running az right angle TO
the shore line the ship takes sOUndines
every mile eastward until a depth of
100 fathoms is reached, These right
angle lines of s0undings are taken a
mile apart the entire length of the coast
/ The inshOre sOundings, where the water
is too shallow for the ship 10 venture,
are taken from small boats at points
| half mile apart
When the lead is thrown. a specimen
of the bottom is brought up by it, and
/ the character of the deposit is recorded.
| It may be mud of some color or coll
Ored sand or shells. All observations
| are noted and when the mariners chart
is issued, any skipper passing over the
scene of the survey could by dropping
his lead and Gscertaining the nature Of
the oceans bottom. tell approximately,
from the record on the chart, the posi-
I tion of his ship when other channels Of
/ Information might. by reason OF fog or
| other circumstances. be closed to him.
The The-is makes 40 to 80 sOundings
/ daily or about one every 10 minutes,
/ and journeys 40 TO 80 miles in the work.
The lead weighs 40 pounds IL is at
tached TO a reel holding piano wire on a
I rapid-acting hosting engine. The OBJ
servers on the ship note the signal
I points on shore through their instru-
I ments. and the ship is stopped at the
right moment The lead rushes to the
sea bottom and the depth is recorded on
q dial Hour after hour this operation
I is repeated a patent log being used TO
assist i'm determining the correct posi-
tion of the ship, and this position is
/ plotted on the chart
Expeditions 10 inland peaks to estab-
/ fish signal stations are frequently nee
/ eSsary.
b I'm triangulating the heliotrope is re-
/ quired. This instrument embraces the
/ principles of the Photograph used in NIL
/ itary signalling BY means of power
/ ful telescope the helOtrOpe operator en-
/ one mountain ton gets the steady reflec-
/ tiOn of the sun from the mirror Of
/ heiiOtrOpe on another peak The ex-
change of these sun signals is made
AT angles indicated on the scale Of the
heliotrope. and from these angles the
/ desired deductions are made by the sur
yeyors. Thus surveyors 90 miles apart
have exchanged heliotrOpe signals, and
a triangle has been established. one slae
of which was 90 miles long. Probably
that is the longest distance exact tri-
angulatiOn which has ever been accom-
plished.
The Thetis is supplied with excellent
boats built especially for landing
through the surf. They are sharp AZ
both ends. with very high bows, and
are so constructed that even when filed
with water they viii continue to ride
the most b0isterous seas.
Landing through the treacherOus surf
of the lower California coast is one of
the almost daily dangers encountered
bv tho officers and men. So long as the
sailors succeed i'm making landings
without mishap theydOnOt get ratified"
when the surf threatens to overwhelm
them
I'm making landings the officers are
without maps 10 guide them as to the
shoals and currents. and are often
placed i'm perilous predicaments by the
treaCherOus waters.
Not long ago, when one of the surf
boats endeavOred to cross an uneX-
plored bar. the sea threw the frail craft
into an almost perpendicular position
The sballowness of the water was such
that the shore end of the boat struck
the bar as the great wave threw the
other end upward Consequently the
tremendous force of the sea threw the
boat end over end, splitting out the crew
as If they were so many flies.
The men had a terrible battle for life.
One sailor was drowned. The COM
handing officer was pulled from be-
Meath the waves by plucky bluejacket.
who jumped overheard from a second
surf boat which was closely following
the unfortunate craft
AT other times a cOmbing wave will
break into q surf boat and FIJI it to the
gunwales but, as the boats have air
compartments they will continue to
-.fr, +r,, ,-or-oe o,-on v-han tho MON or.o