520 report— 1879. 



conditions from which these elements of disturbance may be eliminated. Meanwhile 

 it is evident that a continuous brake, capable of being applied simultaneously to 

 every wheel of a train under the conditions which have been enumerated in this 

 memorandum, is a much more practical and scientific method of bringing a train to 

 rest than the old plan of concentrating the brake-power in two or three heavy 

 brake vans placed in different parts of the train, and leaving the rest of the wheels 

 without brakes. 



The advantage which thus evidently ensues from utilising the adhesion of every 

 wheel of a train for the purpose of stopping a train suggests the further con- 

 sideration as to whether it would not be a more scientific arrangement, as well as 

 more economical in regard to the permanent way of railways, to utilise the adhesion 

 of every wheel of a train for causing the train to move forward, instead of 

 depending for the moving force upon the adhesion of one heavy vehicle alone, viz., 

 the locomotive. Experiments connected with the action of brakes on railway 

 trains require very delicate apparatus ; the credit of the design of the apparatus 

 used in these experiments belongs to Mr. Westinghouse. The efficiency of the 

 arrangements for making the experiments is due to the London, Brighton, and 

 South Coast Railway Company, as represented by Mr. Knight, their general 

 manager, who afforded every facility for the use of the line, and by Mr. Stroudley,. 

 the locomotive engineer of the Company. 



6. Gowper's Writing Telegraph. By E. A. Cowper, O.E. 



The inventor described the details of the construction of his writing telegraph, 

 and the mode in which a pen at a distant station was made to write freely, as the 

 operator at the sending station wrote with a pencil at the sending instrument. He 

 explained the necessity that existed for causing the two currents of electricity that 

 conveyed the power to the distant station to increase or decrease steadily and 

 gradually, without any sudden large increase or decrease of resistance being 

 opposed to such currents ; the construction of the necessary resistances being 

 practically that of one very long thin German silver wire, having 32 thin metal 

 plates soldered to it, at the proper intervals (varying greatly), such plates being 

 all brought very close together, with insulating sheets of paraffined paper 

 between them, so that a contact rod in connection with a battery, with a small 

 knob or projection on it, could slide over the tops of the plates, and make contact 

 with each one in succession ; making contact with one before it left another, so 

 that the small resistance due to the length of wire between two plates was all 

 that was added each time that the projection passed from one plate to another. 

 Then two such contact rods, jointed to the pencil of the operator, and placed at 

 right angles to one another, worked over the tops of two separate sets of contact 

 plates, each set affecting one line wire, so as to give (so to speak) latitude and 

 longitude of the pencil of the operator at all times. 



The quick action or perfect response of the needles at the receiving instrument, 

 which directly controlled the writing pen, was obtained by using exceedingly thin 

 soft iron plates, both for the needles and for the magnets which affect the needles, 

 so as on the one hand to have the least possible amount of momentum and vis 

 inertia in the needles, and the least possible residuary magnetism in the magnets. 

 The needles were slightly curved in their section to stiffen them, their thickness 

 being only j±- inch, and were mounted on polished hard steel bearings, in the 

 manner adopted for the balance wheels of watches when jewelled, and were thus 

 exceedingly free and lively, as a very small amount of friction or weight in this 

 part of the instrument would be fatal to good writing. The power of the needles 

 was insured by fixed flat coils that surrounded them, brought into action by a local 

 battery, whilst the two fine wires were coiled around the fixed magnets that 

 affected the needles, and attracted them more or less, as the strength of the 

 currents varied. Then the needles being at right angles to each other pulled the 

 pen in the two directions, vertically and horizontally, and also pulled against two 



