Bilge-wa-ter a-arm.
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Nautical.) The ordinary form of these alarms is a well in the hold and a float whose rise is made to free an escapement and sound an ordinary clock-alarm mechanism.
In many cases the stem of the float is either graduated to show the hight of the water or has a rack which operates a spur-wheel and turns an indicator-finger on a dial.
These may be read a occasion requires, but are not properly alarms unless with them is associated a device to call attention to the condition of the apparatus.
One form of bilge-water alarm has a vertical rectangular box
A permanently placed in the water whose rise is to be announced.
The float
B rises with the water, and its stem
B has an oblique slot
b, in which a pin moves and gives motion to a bar
C connected to clock-work.
The latter is placed in any convenient position, and connected to the bar by wire or rods, so as to trip the escapement of the clockalarm when the float reaches a certain hight.
The figures represent, respectively, the indicator-dial, the slotted stem and moving bar, the clock-work, and a vertical section through the float and the lower part of the trunk.
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Hydraulic indicator. |
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Leak-alarm. |
In another form a tube is bent to conform to the transverse sectional shape of the vessel, and is provided with a whistle at each end. At the lowest midship portion the bilge-water is admitted at a gauze-covered opening.
When a considerable amount of bilge-water has collected in the pipe, the rolling of the vessel causes the water to expel the air at alternate ends of the pipe, and sounds an alarm.
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Bilge-water gage. |
