The daily gazette., 1880-02-19
A Friend In Need.
A YOUNG JAPANESE ENGINEER INvEETa
AN INSTRUMENT FOR WHICH SURVEY
nRa w IIg. ~ a N HIN

| A YOUNG JAPANEsE ENGINEER INVENT
| AN INSTRUMENT FOR WHICH SURVEY
oRs WILL THANK HIN. nrsls ftAf
1t 10 stated that very curious instru.
| ment, and one that will be eagerly wei
| coined by civil enRiusers and Surveyors,
has been invented by Mr.. T. A. Mats
daria, Of Toxic, japan, young Japan.
Csc enlineer, recently In the employ OF
the Metropolitan Elevated Railway, In
New York. Mr.. Maisdaria, who came
" this country in 1870, i the first civil
/ engineer of Japsuese birth ever employ
ed IN professions' capacity In this
sountry, and has been engaged upon the
II fie Instrument he has Just perfected
{ sevs . ears past. 1t II familiar
fact to those Acquainted with the prob
lens OF surveying and engineering that
tie most tedious calculations associated
with professional services Of that class
arise from the method of MANIPULATION
now In use, and from the fatiguinx and
abstrase relations OF sines and cosinee
which en- or iato the werk. The neces-
sity Of an instrument capable OF meas
urinR these relauons with accuracy, and
of experimentally solving the problems
Of tr1gonometry aris ng IN the course of
survey, has been long confessed by
engineers; but just how such an instrd-
ment was to be adapted 10 the Dscessi-
ties Of the case has not been SO evident.
The invention constructed by the young
Japanese eDgineer-not patented by the
way-consists primarily OF steel or
brass plafe. near the bottom Of which is
q graduated bar which may represent
. 10 base OF any given triaLfl. The bar
Is graduated int0 ten 'qual parts with
extreme accuracy, anu those sections
are again graduated until linear regis
Ter Of The most conceivable fneness Is
produced, At one end of the bar 10
ference of wbi3h Is graduated into de-
grees, minutes and seconds, and the base
Of witch is parallel with the bar itself.
At the other end Is placed a quadrant, or
quarter Of q circle, graduated In the
same manner. At the centre Of each of
the circles, OF which these plates form
sections, u movable bar turns upon
pivot in the same manner as the hands
Of a clock. Each OF these bars 10 gra6u-
ated into ton equal parts of the same
length Of those Of the bases, aud each
part Is finely subdivided. The quadrant
and semi-circle plates are also so con
structed as to slide upon the fixed ibar,
thus forming base hne of convenient
or assig nable length. With this Instru-
ment such pr ,blems as those in which
one angle and the adjacent sides, one
side and the adjacent angles, or one
angle and the opposite side are given to
hnd the other factors, may be performed
instantaneously without calculation.
Having, for example, one and the adj :
cent sides given, the engineer revolv, 9
he graduated bar upon the quadrant u
the angle Is less than q right angle, and
upon the semi-oirole If it Is oblnse, until
the proper angle is registered. He then
revOives the second bar until q triangle
u formed whose sides are exactly pro-
p ItioDate to those gwen. and reads of
gIe second angle from the plate. To find
{ 10 third it 10 then only necessary 70
suOstracL the sum of the two already as
csrtained from 1S0. In the meantime
the ratio Of the third side to the other
has already been registered upon the
second movable bar. The problem is
consequently solved without references
TO the sines. cosines and tedious logar-
lthms with which trig0noneiry abounds;
and II the graduation of the bars, quad
rant and semi-cir Gle Is accurate, the So
luton is NJ exact and unquestionable az
that of q ma hematlcal calculation, al
though performed in possibly less than
twenty seconds. Besides this curious
aud valuable Contribution to mathemati-
cal instrum cuts, Mr.. NJ 4tsdAria has near
ly flushed math- NAUTICAL work of vast
lib0r en'itle1 Loci in Space, which will
extend thu rouRh three volumes. IL has
received the highest encomiums from
mathen icians who have examined
it.