Evening star. [volume] (Washington, D.C.) 1854-1972, 1915-09-26
WHAT THE GOVERNMENT Is DOING

the children that are brought to her a
thorough overhauling. filing out
careful report to the parents.
become II the work were done by all
school physicians Is indicated by the
popularity of the San Francisco demon
stration. Except for the portion of
time that is kept vacant for the benefit
Of some Of the visitors. the time of DR..
Bradley is booked fully until the close
OF the exposition and applications are
received daily. Many parents. who
learn OF the examination on their visit
to the exposition, arrange to return
later with their children In order that
they may secure exact knowledge as to
their condition.
At the same time the general public
has taken a great interest In the work.
and 1t is reported that scores of faces
are pressed against the glass walls
throughout the day as pink and pale
babies sturdy and wan youngsters are
examined. 1t has been reported to the
bureau that in many cases invaluable
a result of the close scrutiny given by
the physician. and that. acting on 1t,
they have in q number of cases already
greatly improved conditions.
While the roller-top desk has almost
passed from the government service.
the "roller top
Roller-Top Dam dam" is coming
Construction. into use Isl, ~, In Co Colo To-
river project. the United States recla-
nation service is putting the finishing
touches on the first complete dam Of
the roller type to be constructed in the
United States. Work is under way.
however: on a roller dam in the state
Of washington for a private water
company, and one roller has been in
stalled for more than year across a
logway of the dam of the Boise project
Of the reclamation service.
The roller construction is a unique
but effective water gate device for con-
els OF reservoirs. A masonry or con-
crete weir is constructed across the
waterway, and at intervals piers are
built. Between these are placed the
steel with toothed ends. When the
rollers are rotated by means Of a
motor and cables wound about them
the teeth operate in inclined racks
placed in grooves in the piers, and
the rollers are lowered or raised.
height of the dam. and when raised
water passes between them and the
weir. Connecting the tops of the piers
is foot bridge. and the hosting mech
Is OF dfidu6Su Ihdt al case VI
emergency the rollers can be operated
by hand winches. When the rollers
are down the force of the water Keeps
them in place and closes joints tightly.
At the Grand river dam the weir is
o46 feet long. and on it are superim-
posed seven rollers-six 70 feet long
and 10k feet in diameter. and one 20
feet long and 15E feet in diameter. By
use of the rollers. therefore. when the
dam is completed the level of the lake
can be kept practically at any desired
point within a range OF over ten feet.
The roller type dam was adopted for
use on the Grand river project after a
careful study of local conditions and
available kinds OF gates. One of the
chief considerations was that an i'm
portant railroad runs along the bank
Of the river above the dam. only few
feet above the water level, and must
be protected from overflow.
The unique type of roller dam origi-
mated in Germany in 1909. and has
crown in popularity in recent years.
The reclamation service has found that
among the good points Of the roller
gates are the possibilities for using
large spans and depths. the absence OF
obstruction to debris and ice when the
gates are open. their rapid operation.
durability and stability. small leakage
and low maintenance and attendance
charges. A unique virtue that the
dams have been found to possess in
Scandinavia is that small furnaces may
be maintained in the hollow rollers in
winter. and so prevent damage to the
mechanism by the formation of ice in