158 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



34 Slight safety pings, at 8 cents $1 92 



G G-liglit safety plugs, at 8 cents 48 



4 20-ligbt safety plugs, at 8 cents 32 



2 40-liglit safety plugs, at 8 cents '. 10 



5 key sockets, at 92 cents 4 GO 



1 wire shade-bolder, at 10 cents 10 



1 pound insulation compound, at 12 cents 12 



2 deep-sea lamps, at $1 2 00 



2 attachment plugs, at 40 cents 80 



3 pounds jSTo. 14 insulated wire, at 40 cents 1 20 



1 pound Xo. 20 insulated wire, at 40 cents 40 



G cigar-lighter plugs, at 55 cents 3 30 



1 new valve 5 00 



1 pressure regulating valve 55 00 



1 new cross head 25 00 



Shortening the belt 3 95 



Amounting in the aggregate to 231 23 



This does not include the cost of lamps and shades, which do not 

 come in my department. Deducting the cost of the piston valve, pres- 

 sure regulator, and cross-head [incident to an original error"], and also 

 the cost of the deep-sea lamps, cigar-lighter plugs, and attachment 

 plugs, which do not form i)art of the ship's illumination, leaves the 



cost of the light, in candle-power, per hour ( ^^ = ) 0.0234 



^ ' 1 ?i V1592.75x47x8 J 



cents. This is less by about 40 per cent, than the bare cost of an equiv- 

 alent amount of gas-light in Washington City. 



The steadiness, brilliancy, and convenience of the light is all that 

 can be desired, while its hygienic advantages over gas or oil-lamps is 

 very great. When it is remembered that an ordinary gas-jet consumes 

 about as much air as six men, and that the breathing-room per capita on 

 board ship is so contracted, tliere ceases to be any comparison between 

 our incandescent electric light and all other means of illumination 

 viewed from a hygienic point. The convenience of being able to light 

 a lamp without fire is great, and the safety of the system, especially 

 at sea, makes it very valuable. The cheerful appearance of the in- 

 terior of the ship when thus illuminated, as comjjared with the interior 

 of other ships lighted with oil-lamps, marks a most agreeable contrast 

 and goes far towards lightening the burden and easing the yoke of a 

 life at sea. 



Our sub-marine lamps have been useful in attracting amphipods, 

 squid, young blue-fish, silver-sides, &c., into the nets, when used near 

 the surface. 



