348 



NATURE 



{Feb. 28, 1878 



follow down the '"' starting " wire from the central station, 

 were twenty or thirty instruments set in action simulta- 

 neously ; that nearest the central station will record first, 

 and as, in the act of recording, it becomes a terminal, 

 the remainder will follow in the order of their distance 

 along the " starting " wire from the central station. Thus 

 were twenty fires to occur in a district at the same time, 

 and twenty " call" instruments were to be simultaneously 

 put into requisition, the whole twenty would record their 

 several messages without interference at the central 

 station, following one another in successive intervals of 

 time, determined by the automatic failing of the weight 

 on to the circuit poles a and b. Now, as this interval of 

 time for each instrument is about three seconds, the whole 

 twenty messages would be automatically recorded in 

 about one minute, or less time than it has taken to read 

 the account of what would take place. 



We have now traced the action of the " starting " wire, 

 which may be stated to perform its functions mechanically 

 by the act of raising a weight momentarily placing it in 

 circuit with the instrument, which becomes immediately 

 a terminal station ; and again by the falling of the weight 

 the instrument is thrown off, and the through circuit along 

 the " starting " wire restored. 



We proceed to examine into the action of the second 

 or "transmitting" wire, and explain the process by 

 which, on the starting of the instrument, this picks up 

 automatically the message, and, after transmission, re- 

 sumes its continuity as a through metallic circuit in rela- 

 tion to the other instruments on the line. 



It will be seen, by reference to the diagram, that until 

 the moment that the instrument is thrown on to the circuit 

 of the " starting " wire by the raising of the weight, w, 

 the through continuity of the " transmitting " wire is 

 maintained as indicated by the arrows ^ — >-, and that 

 the instrument is completely cut out of the circuit. Now 

 the act of starting the drum, D, by the action of the 

 '■starting" current, sets in motion, by the force of the 

 descending weight, the small train of wheels before men- 

 tioned, the uss of which is to give motion to the disc, T, 

 bearing the code message upon its circumference. This 

 disc makes exactly one revolution in the interval of time 

 occupied by the falling of the weight, the distance between 

 the springs, s s', and the circuit contact, a b, upon the 

 restoration of which, the drum, D, is again locked by the 

 detent, E, and the message disc has assumed its normal 

 position. 



We will now trace the action of this message disc. 

 The through continuity of the transmitting wire, when 

 the disc is at rest, is maintained by the pressure of the 

 lever, L, upon the two circuit springs, F. This pressure 

 is exerted so long as the disc is in position by means of 

 the insulated stud, f, upon which the lower end of the 

 lever, L, rests. The moment, however, that the disc, T, 

 revolves, the lever, L, falls back upon the pin, r, the con- 

 tact between the springs, F, is broken, and the transmitting 

 wire is thrown to earth, through the disc. As the end of 

 the lever, L, comes into metallic contact with the " make " 

 and " break " prominences upon its circumference, currents 

 flow to the central station along thecir.^u^t in the direction 

 indicated by the dotted arrows. Nov as these currents 

 are passed in groups to represent letters and words, a 

 code message, or any code message out of a given num- 

 ber, may be automatically prmted at the receiving instru- 

 ment at the central station. In the example given, the 

 currents passed are the Morse signals, indicating the 

 position of the calling station, namely, MAIN St., Gor- 

 BALS, which would at once inform the central station of 

 the exact locality of the fire. The weight once more at 

 rest, the transmitting wire is no longer to earth at that 

 call station, but is again thrown into circuit by the contact 

 of the springs, F. 



From the explanations given, several very important 

 resulis have been estabhshed. Every instrument while 



transmitting a code message is for the moment made a 

 terminal station, all other instruments on the same circuit 

 being thrown off so as to avoid all possibility of inter- 

 ference. At no time is any greater resistance thrown into 

 the circuit than that of the single instrument employed to 

 transmit the code message. Again, only a very small 

 amount of battery power at the central station is required, 

 only one instrument being in action at the same time. 

 Whatever number of instruments on a circuit may be 

 called into requisition at the same time, they will all 

 automatically record their messages one after the other in 

 succession, commencing with that nearest to the battery 

 station, and be all automatically started and brought to 

 rest, without any mechanical complication of parts or 

 delicate electrical adjustments. Such results have never 

 before been obtained and at once place the auto-kinetic 

 system in advance of every other. 



A general description of the apparatus, as placed in the 

 hands of the public will now be comparatively easy to 

 understand, and the stability and simplicity of its construc- 

 tion at once recognised. 



A messenger presenting himself before any one of the 

 street pillar " call stations " will, on opening the iron door, 

 find a dial plate on which some eighteen or twenty printed 

 sentences are enamelled in bold characters ; first, the 

 name of the street indicating the position of the " call 

 station," as in the example given — " Main street, Gorbals " 

 — and following in rotation others, such as " warehouse 

 on fire," " dwelling-house on fire," " mill on fire," " theatre 

 on fire," "send more assistance," "fire got under," "police 

 constable needed," &c. Opposite to each message will 

 be found a substantial knob or handle, something like the 

 " draw-stop " of an organ. The pulling out of the handle 

 opposite the particular code message required causes the 

 instrument to transmit that message to the central sta- 

 tion, where it is printed upon a self-recording Morse 

 receiver ; and intimation is given to the inspector on duty 

 of the arrival of a " call " by the ringing of a bell during 

 the time the message is being printed. The description 

 previously given of the interior construction of the instru- 

 ment will readily explain that the pulling out of the handle 

 simply raises the weight, and that the final ti'ansmission 

 of the message is indicated by the return of the handle 

 to its normal position upon the descent of the weight. 

 As any number of code message discs may be mounted 

 upon the same shaft, and as each disc would have its 

 special make and break lever acting upon the circuit 

 springs, F, there is little additional complication in the 

 internal arrangement from a plurality of code signals being 

 introduced, the working parts being mostly common to 

 either one or twenty discs. The advantages above 

 described are not the only features of im portance in con- 

 nection with the auto-kinetic system. 



A corporation carrying out such a system as described 

 for street police,'and fire " call stations," may derive a 

 considerable annual revenue from introducing special 

 " private fire call " instruments into all the large mills, 

 warehouses, works, and more important private dwellings 

 at a small annual charge to the respective owners. As 

 the number of such " private call " stations introduced 

 upon the circuit is practically without limit, irrespective 

 of the money return to a corporation in a commercial 

 view, the great security to property against any very 

 serious loss by fire is a matter of vast importance. It is 

 well known that the annual losses by fire amount to 

 enormous sums, and often thousands of pounds may be 

 lost by a few minutes' delay in giving early intimation of 

 the outbreak to the brigade. 



The auto-kinetic system of using the two wires whereby 

 only one speaking instrument can be in circuit at a time, 

 renders them likewise peculiarly adapted for the employ- 

 ment of the telephone in introducing a social system of 

 communication between offices and works, or for the 

 legal profession between the courts and their various 



