One end of a copper rod, placed
outside the building, is secured to a bracket, and the other end is
attached to one arm of a weighted elbow lever; to the other arm of the
lever is secured a rod which passes into the building and operates a
valve in the water-pipe. By means of turn buckles the length of the
copper rod can be adjusted so that before the temperature reaches
the point at which there would be danger of the water in the pipes
freezing the valve will be opened to allow a flow of water; beyond
this point the valve opening will increase and the flow become more
rapid as the cold becomes more intense, and as the temperature rises
the valve is closed. This plan sets up a current in the pipes, which
replaces the water as it grows cold by the warmer water from the main.
Destructive Work of Barnacles.--Unless some paint can be found which
is proof against barnacles, it may be necessary to sheath steel
vessels with an alloy of copper. An attempt has been made to cover the
hulls with anti-corrosive paint and cover this with an outside coat
which should resist the attack of barnacles. Somehow the barnacles
eat their way through the paint and attach themselves to the hull. The
vast item of expense attached to the dry-docking of steel ships makes
this matter a not unimportant one. The barnacles interfere greatly
with the speed of a vessel, and in a cruiser speed is of prime
importance. They attach themselves in an incredibly short time to a
steel hull, and it is not long before their effect can be noted by a
comparison of the reading of the log.
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