The Hawaiian gazette., 1872-07-03

procure instruments and to make beginning
Accordingly correspondence was opened with th
Superintendent Of the Z. S. Coast Survey an'
other scientific gentlemen, and an order for in
strumeuts was forwarded to the celebrated firm
Of Trcughton & Simms Of London.
Professor Pierce, the Superintendent OF thu
U. S. Coast Survey and Professor Hilgard, hi
first assistant, have taken much interest in thu
undertaking. and have rendered material assist
ance both By furnishing valuable information il
regard to the best methods, and BY the loan o
/ instruments.
Among these were - inch repeating circle
BY Simms, long used BY the late Edmund Blum
in the primary triangulation OF Chesapeake Bay
twenty years ago. Al the same time they sent
complete set Of the apparatus used il measur
ing subsidiary base lines, which cost originally
$500 These instruments were shipped from
Washington in March ISL, but did not reach q:
till the middle OF the following July BY way Of
Auckland & Sydney.
In the mean time the Superintendent Of the
Survey with bis assistants made reconnaissance
Of West Maui, Kahoolawe, Lanai aud MolokSi,
selected the primary stations and erected signals,
length, crossing the isthmus of Maui nearly at
right angle, the northern end being feet and the
southern l64 feet above half tide. After grading
and clearing the line and making preliminary
measurement with long wire, the final measure
ment with the rods was commenced August 18th
and finished September sth. The mean temper
allure Of the bars during the whole measurement
was "a Fair The last half mile OF the line
crossed travelling dune Of sand and salt
marsh, both Of which were bridged with row Of
piles, which were aligned with transit and dri-
ven down till their tops we're in a straight line, in
order to form solid support for the bars. The
probable error OF the measurement is believed not
to exceed an inch.
A long and aborious series Of astronomical
observations had then to be made, to determine
the true bearing Of the line and the latitude and
longitude of its extremities. The true bearing
Of the line was determined by observing at one
end the angle between the North Star aud Ian
tern set on the other, miles distant, and noting
the exact time by chronometeF.
The difference of longitude between. these sta
tons and HOnolulu was determined BY compar-
ing the local time with that of chrOnometers
carried repeatedly back and forth between Homo
lulu and Eahului
The next series Of operations was the measure
ment Of all the angles of the principal triangles
OF the laborious and delicate nature Of this ope.
nation no one can form 80 adequate idea, who has
not tried to determine angles 10 second, and it
was greatly hindered by unfavorabe weather.
The instruments ordered from Troughton &
Simms did not arrive till November, year after
they had been written for. but proved to be first
class in every respect The large transit theodo-
lite which cost $500, is truly magnificent iu-
'trumeut, with horizontal 10 inch circle reading
10 one second by two mieroneter microscopes,
md vertical circle reading to 5 seconds by two
-erniers.
1t is completely fitted for night observations
u stars with lamp. rehectors, &c 1t is mas
erpieoe Of which Simms may justly be proud.
\ duplicate Of it has since been made for the
Tnited States Government The telescope has
enerally been used with magnifying power Of
6, and is remarkably clear. A bare signal pole
as often been distinguished with it at 8 distance
{ over 20 miles. Two excellent mountain ba.
ometers were received st the same time from
'roughtOn i Simms, and the elevation of great
lsny points has been determined with them.
In the course Of the survey last December
ation was occupied for week on the summit
Haleaksls the elevation Of which was deter
lined both by triangulation and by the barome-
rs 10 be lO0S0 feet. Tie first FIVE triangles I
ere carefully tested 10 various WAYS, and the .
rObable errors Of the angles average considerably 1
s than a second In February last the work .
triangustion was suspended for the present,
ID special survey commenced of the district I
cluding Mskssso, Hsmskuspoko and Hail.
aile. Every house. road, stone wall, gulcb, &c,
as carefully located by actual survey, sll the /
oval Patents and other land titles examined and .
Gated on the ground, and the more important
Nucle u1hed IL pStAi1ueut WauuSi' W.
aps, one Progress Sketch" of Maui and the
sighboring islands. and the other large map Of
e Maksvao district on s scale Of 1000 feet to
e inch. have been laid before the Legislature,
give the members clearer idea of the objects
ID character of the Survey.
The surveying party have just completed the
easurement Of the base line for Oahu os the
ain east Of toEB. The length Of this line is
90 feet Professor Alexander proposes to
mplete the trisngulsiion Of Southern Oahu this
inner, and in September or October to nea-
re the third bzse line on the Waimea plains in
ortheru Hawai-.
speech of His Ex. c. q. Harris,