June lo, 1875"] 



NATURE 



(the other pole being to earth) pressed upon the paper 

 ribbon. As the ribbon was drawn forward whenever a 

 perforation passed the point of the style, metallic contact 

 between the battery and line wire was momentarily made, 

 and a current transmitted to the distant station, the dura- 

 tion of the current being regulated by the length of the 

 perforation in the paper— thus giving the dot and dash 

 code. The message at the distant station was printed by 

 chemical decomposition. A ribbon of paper, prepared by 

 immersion in a solution of sulphuric acid and prussiate of 

 potass, was drawn over a metal cylinder in communica- 

 tion with the earth, and pressing upon this chemically 

 prepared paper was a metal style in connection with the 

 line wire. When, therefore, a current is received by reason 

 of the metal style at the 

 J transmitting station pass- 

 J ing a hole and joining bat- 

 tery to line, the chemical 

 preparation of the receiv- 

 ing ribbon is momentarily 

 decomposed by the action 

 of this current, and a 

 darkish blue mark will ap- 

 pear on the paper ribbon 

 of a length — either a dot 

 or a dash — corresponding 

 to the duration of the trans- 

 mitted current. 



William Sykes Ward's 

 patent, by which signals 

 were indicated by the de- 

 flection of electro-dynamic 

 coils over the poles of fixed 

 permanent magnets, al- 

 ready noticed (Fig. 18), 

 followed in 1847. This 

 patent became, in common 

 with most others, the pro- 

 perty of the Electric Tele- 

 graph Company by pur- 

 chase. 



Holmes's new form of 

 coil and needle, introduced 

 in 1 848, dispensed with the 

 inertia of the long five- 

 inch astatic needle com- 

 bination and great coil 

 resistances of the existing 

 double needle system, and 

 combined a greatly in- 

 creased speed of trans- 

 mission with a reduced 

 battery power, both results 

 of vital importance. This 

 modification of the asta- 

 tic needle combination is 

 shown at Fig. 31, drawn 

 ' to actual size, as compared 

 diamond needle ar- ^ith the fivc-inch needle. 



diSDensmg with the rr^, . . . -i i ^ 



astatic needle combination (b) and re- ^ he next patent brought 

 ducing the resistance of thelcoils. 1848. under noticC, that of Mr. 



W. T. Henley, led to the 

 first serious opposition against the monopoly of the 

 Electric Telegraph Company. In 1848 William Thomas 

 Henley and George Foster brought out their improve- 

 ments in electric telegraphs : this patent gave rise to 

 the formation and establishment of a formidable rival 

 in public favour to the Electric Telegraph Company, 

 viz., the English and Irish Magnetic Telegraph Company. 

 The improvements under this patent consisted in acting 

 on a magnet, to the axis of which is attached an index or 

 pointer by a single electro or other magnet, having each of 

 its extremities converted or resolved into two or more 

 poles. Fig. 32 shows the magnetic needle suspended 



Fig. 31. — Holmes' 

 rangement (a), 



between the poles of an electro-magnet, a, each pole 

 being fitted with a piece of iron, of a segmental form, 

 developing two similar poles. This magnetic needle is 

 deflected in one direction for any length of time required 

 by an induced magneto-current, it being brought back to 

 its normal position by the reversed inductive current. 

 The necessary magneto-currents to actuate the needle are 

 produced from a magneto-electric arrangement consisting 

 of two coils. A, A (on an armature), which are mounted 

 on an axis, H, between the poles, M, M, of a permanent- 

 magnet, and free to move in front of those poles upon 

 depression of the handle, G, in such a manner that one 

 pole of the magnet is not released from its opposition to 

 the armature until the other just touches it, by which 

 means currents of equal power and in opposite directions 

 are produced. This arrangement of parts is shown in 

 Fig. 33. These several representative improvements, 

 selected out of the vast numbers that crowd the field up 

 to 1848, will be sufficient for the purpose of tracing the 

 Progress of the Telegraph, 



Such were some of the instruments already invented 

 when electrical communication was inaugurated in this 

 country by the Electric Telegraph Company. 



Proceeding down the cul de sac known as Founders 

 Court, Lothbury, a stone fagade, with the words " Central 

 Telegraph Station " sculptured in bold letters, and mas- 

 sive oak doors, arrested the attention of the visitor. On 

 entering, a noble and lofty hall with an enriched glass 

 roof presented itself to view, with two long counters, one 

 on either side, for the receipt and payment of rnessages. 

 Behind these counters glass screens were placed with the 



Fig. 32.— Henley and Foster's Magneto-Telegraph, 1848. Indicator 

 movement. 



names of the several stations open for messages painted 

 in black letters upon them, the instrument rooms being 

 behind the screens upon either side. 



The west side of the hall was devoted to correspondence 

 with the northern and western districts, and the east side 

 with the eastern and southern districts. Additional instru- 

 ment rooms were provided on the first and second floors at 

 the sides of the hall ; and at the time of the opening of the 

 station to the public, the Company had access to about 

 sixty towns, with an extent of single wire along the rail- 

 ways of some 2,500 miles, and had a telegraph staff of 

 fifty-seven hands appointed to the Metropolitan Station. 

 The battery rooms, testing boxes, earth connections, and 

 the tubes for bringing the wires into the building were 

 situated in the basement underneath the great hall. The 

 various wires were brought along the streets in pipes 

 beneath the pavement. Twenty-seven came from the 

 North Western Railway, nine from the South Western, 

 nine from the South Eastern, nine from the Eastern 

 Counties, nine from the branch office, 345, Strand, in- 

 cluding those from Windsor, nine from the Admiralty, 

 which with nine spare wires completed the circuit 

 arrangements of the Company at the time that the tele- 

 graph was thrown open to the public. Many of the 

 railway companies continued to reserve the use of their 

 telegraphic lines to themselves ; the Telegraph Company 

 from the central station had therefore no power to forward 

 public messages over such districts. 



It is natural to suppose that great excitement and 

 anxiety existed amongst the directors with reference to 

 the opening of the building to the public for the receipt 

 and transmission of messages. The disturbed state of 



