Making a Life-Saver of a Leak 



WHEN a heavy sea is running, one 

 of the glass-covered portholes in 

 the bow of a steamer is often 

 crushed in — an accident which, while 

 seemingly unimportant, has resulted in 

 the foundering of many a ship. Water 

 rushes into the opening at the rate of 

 many gallons a minute. Should the 



The water tank covers a hole in the 

 ship's side. Part of the interior is shown 

 so that the balancing-chamber can be seen. 

 The small tube at the top leads to the 

 mercury gage which tells whether the 

 ship is listing or not 



crew be occupied in other parts of the 

 ship in clearing decks or battening down 

 hatches, the broken port is likely to 

 escape notice until enough water has 

 entered to make the situation really 

 serious. 



An automatic registering device with 

 a dial in the chart room or captain's 

 cabin has been installed on several 

 freighters, to indicate within a fraction of 

 an inch exactly how much water the 

 vessel is drawing both forward and aft. 

 The instrument has been applied to 

 other uses, such as measuring the depth 

 of rivers and the amount of oil and other 

 liquids in tanks aboard ship and ashore. 

 In all of these applications the principle 

 of the device is the same. 



The natural law which governs the 

 operation of the "pneumercator," as the 

 invention is called, is nearly as old as 

 mechanics. Simply expressed, it is that 

 the weight of liquids having the same 

 cross-section is directly proportional to 

 the depth. 



Described in a few words, the device 

 consists of a pressure-gage, which regis- 

 ters the weight of liquids in which it is 

 sunk, and by means of a tube containing 

 air indicates the pressure on a wall- 

 gage. The apparatus is made up of 

 three essential parts: a balancing- 

 chamber, an indicator and a small 

 pressure-pump. The balancing-chamber 

 is connected by copper pipe line with the 

 indicator, and the indicator is connected 

 with the pump by means of another 

 pipe line. 



A cargo steamer equipped with two pneumercators. The balancing-chambers are contained 

 in the tanks which are indicated in the bow and stem. Holes in the ship's side, which allow 

 the tanks to be filled, are placed a few inches below water line when the ship is unloaded. 



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