56 



SCIENCE. 



[Vol. XIII. No. 312 



The cell employed was the type 19 C of the Julien Company, 

 weighing complete about 44 pounds, which is rated by that com- 

 pany as having a capacity of 200 ampere-hours, and the rate of dis- 

 charge given is 30 amperes. It will be seen, however, that, as these 

 lamps take about /^ of an ampere each, the batteries were being 

 discharged at about twice their normal rate, and, where occasion 

 required, the engine was stopped and the batteries supplied current 

 for the entire plant, thus discharging at almost three times their 

 nominal rate. 



This is a particularly creditable showing for these batteries. The 

 principal difficulty heretofore in the use of accumulators has been 

 that they have not been permitted to be discharged at a greater 

 rate than from about one-tenth to one-eighth of their capacity, 

 whereas in this exhibit they were regularly required to deliver their 

 full capacity in about four hours. 



The cells were in use from the commencement of the exhibition, 

 the 1st of October, until Dec. 15, and did not in that time require 

 the least attention on the part of the company, the plant being run 

 entirely by a man in charge of the gas-engines, who, until the 

 opening of the fair, had never been in charge of an accumulator 

 plant. 



The lights were burned four hours each night, which, dischar- 

 ging at the rate of about 60 amperes, and occasionally at 80 to 85, 

 made a total of 250 ampere hours taken out, while the rated capa- 

 city (discharging at the nominal rate) is but 20Q ampere hours. 

 This is an indication of the large amount of reserve energy there is 

 always on hand in case of an accident or stoppage of the generat- 

 ing-plant, or in case of an emergency. 



A BLIZZARD MEETS AN ELECTRIC ROAD. 



Recently one of the severest tests to which an electric railroad 

 can be subjected was experienced by the Davenport Electric Line, 

 installed by the Sprague Electric Railway and Motor Company of 

 New York, at Davenport, lo., and one which proves most conclu- 

 sively that an electric railway can be operated even under the most 

 adverse conditions of weather. The blizzard, which had been howl- 

 ing about the Dakota prairies during the first part of the week, 

 and getting up its strength by snowing in the territory farmers, 

 decided to come south, and on Jan. 9 struck the city of Daven- 

 port. 



The snow, which was of the heavy damp variety, fell all day, and 

 covered the streets to the depth of from four or five inches to one 

 foot on a level, and in several places caused deep drifts over the 

 line of the electric railway. In spite of this, the cars on the electric 

 line kept running uninterruptedly, carrying a large number of pas- 

 sengers, and proving conclusively that no amount of snow could pre- 

 vent the cars from running on schedule time. The president of the 

 road, Mr. W. L. Allen, was greatly pleased with the signal triumph 

 of the Sprague people, who had told him in the autumn that snow 

 could not interfere with the operation of the road, and is enthusias- 

 tic over electric railways. 



This road has been in operation about four months, and has been 

 giving very great satisfaction to the management and citizens of 

 Davenport, who have had a much better service since its installa- 

 tion than they ever had while the road was being operated by 

 horses. The cars move faster, are under quicker and more perfect 

 control, and are much more easily managed than the cars drawn by 

 animal power. The regular Sprague overhead system, with small 

 No. 6 silicon-bronze wire as a working conductor, is in use upon 

 this road. All the latest devices and improvements adopted by the 

 Sprague Company for facilitating the operation and increasing the 

 convenience of their electric roads are in use here. 



Among the principal points of excellence of the Sprague system 

 of electric railway, may be mentioned the system of conducting 

 current to the cars by means of a working conductor, separate from 

 the main conductor, but connected to it at intervals by automatic 

 cut-outs, by which an accident on any portion of the line does not 

 interfere with the remainder of the road ; the use of flexible suspen- 

 sion for the motors, preventing accident from sudden strain ; and 

 the method of controlling the motors from either platform without 

 the use of idle resistance. 



TESTING A PNEUMATIC DYNAMITE GUN. 



On Saturday last a test was made of the capabilities of a pneu 

 matic gun of fifteen inches bore, forty feet in length, intended tO' 

 throw a shell containing 700 pounds of dynamite and nitro-gela- 

 tine. Two shots were fired, when, owing to the leakage of an air- 

 valve, the experiments were postponed to some future time. As^ 

 far as the trial went, the results were satisfactory. A mile from 

 the gun, which was located at Fort Lafayette, in the Narrows, New 

 York Bay, a rectangular space 50 by 100 feet was marked off in the 

 waters of Gravesend Bay by four buoys. The first projectile from 

 the gun passed about 250 yards beyond the target, though it was 

 an excellent line shot. Its course was easily followed by the un- 

 aided eye from the moment it left the gun until it entered the 

 water. It passed through the air as though shot from a rifled gun,, 

 without an oscillation or a "wabble." It exploded a moment after 

 striking the surface, throwing up the water, like an immense foun- 

 tain, from 100 to 200 feet into the air. This first projectile con- 

 tained 170 pounds of dynamite. 



The second projectile, containing 200 pounds of dynamite and 

 300 pounds of nitro-gelatine, a larger charge than had ever been 

 used before, fell short of the mark, but the effects of its explosion, 

 were tremendous. A reversed Niagara, of water, mud, and stones,, 

 shot perhaps 200 feet into the air. It seemed as though a water- 

 volcano had broken forth in Gravesend Bay. 



The reason for this shell not reaching the target appeared to be 

 that there was some defect in the tail-piece, which is depended 

 upon to keep it from oscillating or wabbling in its flight. Some 

 part of this tail-piece was evidently injured in leaving the gun, and 

 the consequence was that the longitudinal axis of the projectile 

 (which was six or seven feet in length) deviated from the line of 

 flight. It swung through an angle of about forty degrees, back, 

 and forth, while describing the arc of flight, the oscillation decreas- 

 ing as the projectile approached the water. 



Further tests of the gun are promised in the near future, and 

 they will be watched with interest, as the dynamite gun is destinedi 

 to take an important place in the warfare of the future. 



THE RISLEY AND LAKE COMPOSING-MACHINE. 



There is now on exhibition at No. 22 Spruce Street, this city, a. 

 machine intended to dispense with the use of type in certain kinds- 

 of printing. It is the invention of Messrs. Risley and Lake ; and 

 though only an experimental machine, and therefore somewhat im- 

 perfect in many of its details, it does its work speedily and welL 

 The printing done by it is not as perfect or as pleasing to the eye 

 as ordinary letterpress work, but is good enough to satisfy the re- 

 quirements of that important branch of the printer's art known as 

 law printing, in which small editions of lawyers' briefs, legal argu- 

 ments, evidence, etc., are desired in a few hours' time. 



This machine, in its present crude but very promising stage of 

 development, is shown in the accompanying illustration. As a 

 satisfactory description of it cannot be given unless the machine be 

 seen in operation, only a few of its features will be touched upor» 

 here. Though not so complicated as the engraving makes it ap- 

 pear, still many of the mechanical movements involved are so novel 

 that they must be seen before they can be readily understood. 



It will be perceived that there is a key-board like that of an or- 

 dinary type-writer, the use of which is obvious. There is a key for 

 each character used. These characters are all cast or cut on one 

 cylindrical shell or sleeve, in which feature the machine resembles- 

 the well-known Crandall type- writer. This type-shell may be seen,, 

 in the illustration, at the centre of the machine, immediately to the 

 rear of the key-board, and in front of the sheet of paper upon which- 

 the printing is to be done. One peculiar feature of this machine is, 

 that the printing does not begin until the keys for about fifty char- 

 acters have been struck, so that the operator is always at least a 

 line ahead of the impressions as they appear on the paper. The 

 keys, instead of acting directly upon the printing apparatus, act 

 upon a set of pins, which are carried in a revolving disk ; each key, 

 when depressed, setting its appropriate pin in position for actuat- 

 ing the printing mechanism when the disk shall have carried it 

 around to the proper point. In this way there are always stored 



