February i, 1889.] 



SCIENCE. 



tors of the road express themselves as very well pleased with the 

 rsuccessful performance of the motor-cars. 



A New System of Electrical Distribution. — One of 

 the problems which has claimed the attention of inventors in the 

 past few years has been the conversion of high-tension to low- 

 tension electric currents. The object is to distribute electric 

 energy at a high potential, using comparatively small wires, and at 

 the points of consumption to reduce the potential to that de- 

 manded by safety and the requirements of incandescent lighting. 

 A large part of the cost of an incandescent electric plant is in the 

 wires used for distribution ; and the size of the wire required to 

 distribute a given amount of energy varies inversely as the poten- 

 tial used. One of the most successful converter systems is that 



DICKERSON ; 



■ ELECTRICAL DISTRIBUTION. 



used by the Westinghouse Company, where alternating currents 

 are employed, and the reduction is effected by transformers, — in- 

 duction-coils working backward. But there are some disadvantages 

 in the use of alternating currents, and many attempts have been 

 made to invent a continuous-current converter, that will do for 

 continuous what the transformer does for alternating currents. 

 Storage-batteries would offer an ideal method of effecting this, but 

 ■for their cost and depreciation. Several mechanical methods have 

 been tried, among others a motor-generator arrangement, — a com- 

 bined motor and dynamo, the former supplied from the high-po- 

 -tential circuit, the latter supplying current at a low potential to the 

 local circuit. Other plans have been proposed in which the main 

 circuit is interrupted and advantage is taken of its inductive effect 

 on the secondary circuit. None of these systems, however, are 

 in successful operation on a large scale. Mr. Edward N. Dick- 

 ■erson, jun., of this city, received last week (Jan. 22) a patent on 

 an improvement in his method of converting high-tension into 

 low-tension currents. Feb. 14, 1888, a patent was granted Mr. 

 Dickerson for a method of converting a direct high-tension cur- 



rent into an alternating low-tension current ; and by his recent im- 

 provement he is able to obtain a continuous low-tension current, 

 which is a considerable advantage if the resulting current is to be 

 used for a motor or for electric plating. The accompanying figures 

 will make it clear how this result is obtained. A high-tension cur- 

 rent flows out upon the circuit a, and returns to the generator by 

 the circuit k. By the switch L it passes through the motor C. On 

 the shaft of this motor is arranged the double reversing-commu- 

 tator BB, the sections of which are alternately connected with the 

 circuit (/and with the circuity. The current upon the circuits ef 

 is a high-tension reversing current, and operates the converter D, 

 which converts the reversing high-tension current into a reversing 

 low-tension current. This induced alternating current passes to 

 the reversing-commutatoryTf, by which the reversing currents are 

 rectified. It is of course essential that the two commutators shall 

 move synchronously, and the commutator yA' should be so adjusted 

 on the shaft as to allow for the time required by the converter. 

 The switch EF may be omitted ; but by it it is possible to throw any 

 house into circuit from the central office. 



The Westinghouse and United States Companies. — An 

 agreement is reported between these companies whereby their 

 interests are united. The United States Company is one of the 

 oldest electrical manufacturing companies, and has a large factory 

 in Newark, N.J. The Westinghouse Company was already the 

 lessee of the Consolidated and Sawyer-Man Electric Companies of 

 New York, and the owner of the Waterhouse Electric Company of 

 Hartford, Conn., and the Tesla Electric Light and Manufacturing 

 Company of Rahway, N.J. The new combination has a manu- 

 facturing capacity of over 15,000 lamps a day, and the two com- 

 panies own and control about 700 patents in every branch of 

 electrical invention. 



NOTES AND NEWS. 



It is announced that a post-graduate department in electrical en- 

 gineering will soon be established by the trustees of Columbia Col- 

 lege, this city. A beginning will be made upon an economical 

 scale, and the facilities will be increased in proportion to the pat- 

 ronage, which it is believed will increase rapidly, as New York is a 

 city in or near which all or nearly all of the many applications of elec- 

 trical science may be studied in practical operation. The course 

 will be open to graduates of all scientific schools. 



— An electrical exhibition will be held in the Chicago Exposition 

 Building, in connection with the National Electric Light Association 

 Convention on Feb. 19, 20, and 21. Many exhibiters have already 

 secured space, the electric railway companies being especially fore- 

 handed in that respect. The exhibition, though not intended to be 

 of long duration, promises to be interesting and important. 



— T\\^ Journal of the Society of Arts reports the discovery of a 

 new textile on the shores of the Caspian. This plant, called " kanaff " 

 by the natives, grows in the summer, and attains a height of ten 

 feet, with a diameter varying from two to three centimetres. By 

 careful cultivation and technical manipulation, M. O. Blakenbourg, 

 a chemist and engineer, who has made a special study of kanaff, 

 has obtained an admirable textile matter. It is soft, elastic, and 

 silky, gives a thread which is very tough, and can be chemically 

 bleached without losing its value. The stuffs manufactured out of 

 kanaff, and then bleached, can be successfully dyed in every shade 

 of color, and would compete with any of the ordinary furnishing 

 materials now in use. But it is particularly for making sacks, tar- 

 paulin, ropes, etc., that this new textile, from its cheapness and its 

 extraordinary resisting power, might defy all competition. Its spe- 

 cific weight is much less, but its resistance much greater, than 

 those of hemp. Thus, a cord of 8. 25 millimetres diameter, woven 

 with the hand out of three threads of kanaff, requires a weight of 

 1 80 kilograms to break it. A cord half an inch thick, manufactured 

 at Moscow, did not break till the weight of 625 kilograms was 

 reached. When it is considered that Russia annually consumes 

 more than one hundred and fifty millions of sacks, a third of which 

 are imported, it may be easily seen that the appearance of this new 

 textile on the Russian market is an event of no slight importance. 



