Evening star. [volume] (Washington, D.C.) 1854-1972, 1908-10-18
ArRDEL HlpER @AR1E: Or @N7TycN0n

basic material for the models. and after
some difficulty p varnisa was found
which rerders the surface az me wood.
20 all utents end purposes. water-t!ght.
\ twentyfoot model. wEicn is he stand
ard size III the Washington tank. is in
point of dispiacemcnt-and that is what
counts III ,Lese festive times as large
as a twelVe-foot model. such as is used
10y tie foreign eXpcrimentars.
The method az building > model is COM
p&ratiVey simDe. The lines" Of a ship
Invariably include a hody plan giv.ng
sections at moderately close intervals
From this body plan lew sections are
drawn 10 the proper size FOR a twenty
foot model by means of the e:dpgraoh or
& large photograph. These sect 0ns are
cut 0u- on paper and then transferred 10
wooden boards. which are SAVED 10
shape. Next these boards are placed in
their proper relative positions anon an
erecting table, eacf hoard section being
then covered With batIens about half an
inch thick and taper.aS from midshlps
toward the end making Il "former' nod
el the surface OF which i planned smooth.
Niea ~ f;l6 I rui:"'l block az ShaneS and
dimensions. TO eial! : ' -odel
10 be cut from Il. has pec ret and
glued together under pressure in large
hydraulic press Next the material in
hand s turned over to the Woodworking
machine. perhaps the most ingenious OF
the mechanical aids employed. and.
finally. TIE model is removed from he
cutting machine and finished by hand. a
very small amount o. hand work Being
necessary however. Now. the miniature
ship is ready for vanishing ana the at
tachment of hilge keels and any other
APPENDICES. after which II Is taken 10
the measuring machine and careful
measurements made Of the exact form
and shape which not only enable the de-
ternina ton whether the model represents
the lines desired. but give an exact rec
ord or the actual shape
Description of the Bridge.
The bridge or travelling carriage which
spans the tank and moves the models on
their voyages through the basin, runs
upon eight wheels. II the center is
platform carrying the recording APP
paratus which can be raised or lowered.
Electricity Is used 10 drive the carriage.
and It may be mentioned incidentally that
Il is used for all mechanical york in con-
nection with the tank. The speed OF the
carriage is varied not only by making
various combinations of the four motors
one for each pair Of driving "heels-nut
by controlling the output Of the generator
III the power station. Which Is perhaps NV
yards frcm the tank.
The carriage itself with its fittings,
weighs in the ne:ghborhood Of twenty-five
tons so that ii forms a kind or hy-wheel
speed. The speed Of the carriage may
be varied from one-tenth o. a knot per
hour, OF ten feet per minute. 10 twenty
knpfs ner hour or 1900 feet per minute.
The difficulty with high speeds however
is that Of stopping the carriage, once II
is under way
The basin is filed from the water sys-
TEN Of Washington and will hold i,oiNeO
gallons. The leakage from the basin.
which is very slight and the evaporation
are made up with filtered water. an ami
ma bore tlter being installed with a
capacity OF from fifty 70 one hundred
gallons per minute depending upon the
Iurbidty OF the water. In practice a
small stream Of fresh filtered water is
kept running into the basin all the time.
and the level maintained whenever de-
sired by an adjustable overflow. Ii is
notable that not only were the building
and tank at the model basin designed by
he officials OF the Nary Department, but
all OF the machinery. even 20 the electro
cal equipment, was devised by the gov
eminent experts Naval Constructor Tay-
lor has been in immediate charge OF the
work from the outset.