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IMPROVEMENTS IN PHAROLOGY. 171 
the escape of the crew of the lightvessel in case of acci- 
dent. 
Having thus briefly described my proposed plan, I 
wonld observe that I think, that by the gyrations of the 
fly-wheel (about 100 per minute), the peculiar form of float 
which I employ, and the manner in which I moor it, the 
desired object will be attained, that is, the oscillation will 
be reduced to a minimum, and we shall be able, not 
only to increase the intensity of the light by the use of 
the most improved apparatus, but likewise to extend its 
range by adding to the height of the tower. 
It may be objected that the use of an engine would 
greatly increase the expense of maintenance; this how- 
ever would not be the case, as a small engine, with fuel, 
attendants, &c., might be maintained for about £150 per 
annum, even if no corresponding reduction were made in 
the number of hands now employed. I may add that the 
total weight of this floating lighthouse, with all its ma- 
chinery, stores, &c., on board, will be about 300 tons, 
whilst its displacement will be equal to 600 tons; it will 
therefore perhaps be practicable to diminish the amount 
of immersion, and so add to the height of the tower. 
VOL. XV. AA 
