Evening star. [volume] (Washington, D.C.) 1854-1972, 1931-08-20
WATER MEASURED
ON NIAGARA FALLS
Perpendicular ScantIings Are
Floated Down River to
Determine Depth.

Special Dispatch to The ssa-
Ottawa. Cnt2rio. August 2o-Meas1r-
ing CT the water going OYER Niagara
RAJ was an cscntial part OF the re-
cent WORK OF tl1 special International
Niagara Bosr3--a body Of eminent
american and Canadian engineers who
stuulea EoW tle scenic beauty Of Nj
eg "a Falls can best be maintained
Inc comparatively small amount and
even distribution CT the flow roinr over
tns American Falls presented little din
ed4Iy ID ten beard. A light rope vas
snot ACROSS from the New York main
and to Goat Island by means OF A
mortar, then steel cable was hauled
across and frightened. and BY the use
OF carrier system provided with
WeigntS ana meters the discharge fig
nres were secured from which the depth
ana rate OF now over the brink Of the
American falls was readily computed
Serious Problem Solved.
The cccth and rate Of flow over the
brink of the Horseshoe Falls presented
a more serious problem and results
were obtained by means OF floats, which
were made OF scantlings, so buoyed and
weighted as to float perpendicularlv
with submerged lengths Of from / foot
to u feet, and with tagged tops that
could be readily observed from the
shore. These floats were taken out on
the river above the rapids In motor
boats and dropped into the water at
definite points en- a range line across
the river When a float was released.
the watchers on the shore recorded its
progress by transit and stop-watch OBJ
serVatlons, aided by Photographic and
motion picture records. BY these
methods the rate Of flow Of the float
in each section was rapidly determined.
II float went through its course
upright, 1t was evident 1t did not touch
the bottom. Longer floats were sent
through until one dragged on the bot
tom. Then with the length of the float
known and by noting the angle Of In
eIinat!on 1t was possible to calculate the
depth at that point. To secure records
OF the characteristics Of the current in
the rapids adjacent to the river banks
near the falls 1t was found necessary
to shoot the floats from springrguns on
the banks.
How TO Get Best Color.
The board also investigated the cause
and characteristics of the bluish-green
color of the water at the brink and how
this beautiful effect might be height
ened by securing greater contrast with
the foam curtains at the edges and
shallower parts. The color phase il
most effective when seen from across
the gorge. As a result Of the investiga-
ton the board has determined that the
conservative minimum depth Of water
on the crest Of the falls, for maximum
brilliance Of color. Is 5 feet
An interesting feature was the sur
vey of the water surface in the rapids
above the falls by photo-topographical
methods and the development Of q
small-scale relief map and model repre-
senting the water over the entire rapids.
The engineers composing the Inter-
national Niagara Eoard are j. T. john
ston. director of the Dominion Water
Power for Canada. and Mai De Witt
c. Jonas. an engineer of the United
States Army, for the United States.
The members added to form the spe-
cial board we're DR. Charles Camsell.
deputy minister of mines Canada, and
Or. j. Horace McFerlsnd. past presi-
dent Of the American Civic Association
and chairman Of the Art Commission
Of Pennsylvania. the United States.
Copyright, 1912