Heroes of the Telegraph/Chapter 4 > 자유게시판

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The load diagram through the day, however, shows a new station on a clear day with a small number of lights lighted, and power work only just commencing. I do not desire to claim that the ideas for the class of work here represented and described hold or represent all the perfection to be obtained in central station work. Overhead travelling cranes are installed here and in the engine-room for ready and quick handling of all apparatus. I think even here we need to carefully consider the problem as well. The weekly records from stations of this class charge the horsepower output with all the coal used by the engine, pumps, condensers, well pumps, cleaning fires, blowing-off boilers, etc., and where the former item is about three pounds of coal per horse power per hour, we have in the latter case, making no allowance for the engine running empty, a result fifty per cent, what are electric cables greater than this. Assume, for the sake of argument, that we can save five or ten per cent, in steam economy; if this is obtained at a cost, the interest of which amounts to more than this, we are obtaining it for no good whatever; furthermore, there are many other problems in electric light stations which we have to carefully consider in this question of steam plant, one of which has been enumerated before, viz., the question of reliability in operation, and always being ready for service.

The average income per light in stations of this class varies in different parts of the country and with different loads. When there is no current on the instrument, the spot of light remains stationary at the zero position on the screen; but the instant a current traverses the long wire of the coil, the suspended magnets twist themselves horizontally out of their former position, the mirror is of course inclined with them, and the beam of light is deflected along the screen to one side or the other, according to the nature of the current. But before it reached the Red Sea the cable had broken down, and the instrument was returned dismantled, to be superseded at length by the siphon recorder, in which the marking point is a fine glass siphon emitting ink, and the moving body a light coil of wire hung between the poles of a magnet. The first solution to these problems is to keep cable lengths in buildings short since pick up and transmission are essentially proportional to the length of the cable. If one will carefully look over this plant, as I had the pleasure of doing a short time ago with others, and consider all these problems carefully, and then examine & station similar to the Brooklyn one.

Hence the Gorgon, one of her consorts, was ordered to go ahead and lead the way. At a moment when the value of our distant colonies is being questioned by grave professors at our seats of learning, this new instrument of civilisation appears upon the scene, destined, in all probability, to solve many of the difficulties in the way of government which of old the sundering ocean placed in our way. Now, it is very questionable indeed if the old cable (even supposing its insulation to have been perfect) could have worked this paying number. We feel that there is no possibility of things going on for ever as they have done for the last six thousand years. Twenty years before he had seen whips made of it in Singapore, and believed that it would be useful in the fabrication of surgical apparatus. The best operators cannot send over thirty-five words per minute by hand, but a hundred and twenty words or more per minute can be transmitted by an automatic sender, and the recorder has been found on land lines and short cables to write off the message at this incredible speed.

A careful analysis of all the items covered in these expenses in such a station as this one, gives the following result: That the fixed expenses are seventy-five per cent, of the whole, and the variable twenty-five per cent, approximately; or, in language which may appeal more directly to you, if we double our income or business, we only increase our expenses 25 per cent. One of the most important items is the cost of such a plant. Bishop Mullock, head of the Roman Catholic Church in Newfoundland, was lying becalmed in his yacht one day in sight of Cape Breton Island, and began to dream of a plan for uniting his savage diocese to the mainland by a line of telegraph through the forest from St. John's to Cape Ray, and cables across the mouth of the St. Lawrence from Cape Ray to Nova Scotia. Continuous-flex or flexible cables used in moving applications within cable carriers can be secured using strain relief devices or cable ties.