TELEGRAPH. 



it is to remain there till he receives aiiotlicr wor J, and fo on, 

 till all that is meant to be i;ud is iiiiiflied : the pointers of 

 thoufands and units are then to be vibrated backwards and 

 forwards, with the points downwai-ds, like pendulums, till 

 the fame is done at the oppofite ftation. 



if any interruption takes place on either fide from a cloud, 

 or fhowcr, or any accident, it is to be indicated by vibrating 

 thovfands and units, with their points upwards ; which fignal 

 muft be repeated from the oppofite ilation ; and whoever lias 

 madfe the fignal of interruption,, muft make the fignal of 

 recommencement, when he is ready to proceed. This fignal 

 is by vibrating hundirds and /raj-, with their points upwards, 

 and when this is anfwered, (hut not before,) the bufinefs 

 may proceed. It fliould be obferved in general, that every 

 iignal (liould be acknowledged by the party to whom it is 

 addreffed. 



The vocabulary con'efpo;iding with the numbers denoted 

 by this rnachinery is conipofed of a large book, Jig. 13, 

 with mahogany covers, framed, to prevent them from warp- 

 ing. Its fize, when opened, is 47 inches by 21 ; it confifts 

 of 49 double pages, that is to fay, each flieet is folded in 

 the middle, and when it is opened forms one page. 



Tiie book is divided into feven parts by^ thin flips of 

 mahogany, which ferve to open it eafily at each of thefe 

 divifions, every one of which contains feven pages, and 

 each page forty-nine words. No more than forty-nine 

 words are contained in each page, becaufe the numbers 

 8 and 9, and zero, are not admitted. This omiffion arifes 

 from the ftruclure of the machinery, which points only to 

 feven numbers, refcrving o for a point of reft, at which 

 point the hands indicate nothing. In every hundred, there- 

 fore, only forty-nine numbers are ufed ; and in every 

 thoufand, only feven hundreds are counted. Each divifion of 

 the book, feparated by the mahogany rulers, contains all 

 the efficient numbers in feven hundred. Each of thefe 

 rulers projedts beyond the fides of the pages, and is num- 

 bered in fucceffion from i to 7 ; and they are fo placed 



below one another, as to permit ihc numbers on all fides of 

 them to be leen at once, as in llie figure. 



When any number of thoufands is pointed out, it can 

 by means of thefe rulers, be immediately feleded : the feries 

 ot feven pages, which one of thefe rulers opens, is cut, like 

 the alphabet of a ledger, at the edge in feven divifions. By 

 thele means, the page containing the iiundrcd whicli i« 

 wanted is inftanlly found. In the page thus obtained, the 

 tens, from 10 to 70 inclufive, are divided from each 

 other, fo as to be inftanlly diftinguifliable, and the units 

 under, each divifion arc in like manner eafily felcfted. 



The following is a fpccimcn of feveji lines of the firll 

 page, and tliougli it is but one-tenlh of tjie real fize, it is 

 iufficienlly dlftiiift. Its contents arc divided into eight clafies, 

 the words in each clafs being numbered downwards, from 

 1 to 77, omitting all cyphers, or zero, and all eights and 

 nines. Wlien once the clafs required is afcertained, any 

 number in the page can be found iminediately. As f6r 

 inftance, the reader will eafily felect Clafs VII. N°li, 

 Clafs IV. N° 15, and fo of the reft. Nothing remains to 

 be explained but the manner in which the clafs in each page 

 is pointed out by the machinery. For this purpofe, before 

 the pointers are turned to any fet of figures, the pointer that 

 reprefents thoufands is turned to the clafs that is wanted, and 

 as foon as the correCpondent anfwers this fignal, thoufands is 

 returned to o. Then all the pointers are moved to the 

 places which denote the figures required for any word or 

 fentence. When the clafs is thus afcertained, an index, 

 which flides on the maiiogany cover of the book, is fet to 

 the column belonging to this clafs. When an obfervation is 

 made, tlie number of thoufands can be opened by the ruler. 

 As foon as it is read off' by the telcfcope, the number. of 

 hundreds is opened by the pages, where they are cut away, 

 and the number of tens and units is feen on the page. As the 

 pointers are moved in fucceflion from thoufands to units, 

 the different divifions of the book can be opened as faft, as 

 the pointers are moved. 



Specimen of the Vocabulary belonging to Mr. Edgeworth's Telegraph, 



Commnn 

 Words. ■ 

 Clafs 0. 



Wonls lefs 

 CiitniTinn. 

 Clafs 1. 



TcclinicalTerms 



0, n, m. 



Cl.lb II. 



Perfons. 

 CUs III. 



Officers. 

 Cliifs IV. 



Places. 

 Clafs V. 



Navy ami Mer- 

 chant SItips. 

 CIdfs VI. 



Phraffs and Sentences. 

 Clafs VII. 



[U. A. 



1-2. Ab. 



13. Ac, 



I 14. Ad. 



1 .s Ae. 



I16. Af. 

 17. Aa. 



11. Aliafe. 

 \}. Abate. 



13. .'\hbcv. 



14. Ahbcis. 



15. Abliut. 

 Ifi. Abdicate. 

 17. Abed, Abet. 



11. Aback. 



11. Abacus. 

 1-J. Abaft. 



14. .Ab.itis. 



15. Al)d(inicn. 



16. Abdutftur. 



17. Abeal. 



11. Abbot. 



12. Ackland. 

 l.S. Acftini. 

 14. Achefiin 

 1 i. Adams. 

 10. Adamfoii 

 17- Adair. 



11. Academy of Infcript 



12. Acad, of B. L. Paris 

 1 3. Academy. 



14 Account-Office. 



15. Admiralty. 



16. Af;ent to the. 



17. Admiral. 



I 1. Abbeville. 

 12. Aberdeen. 

 1.3. Aberj;avenny. 



14. Abinglon. 



15. Abydos. 

 1(5. AbylTinia. 

 1 7 . Acadia. 



11. Alias. 



12. Ajjx. 



13. Albion. 



14. Africa. 



15. Audacious. 



16. •.Agamemnon. 



17. America. 



, Attend to day 



la.- 



14. - 



15. - 



16. . 



17.- 



- to-morrow 



- to night 



- to-niorrotv nig 



- on Monday 



at A.M. 

 .iP. M. 

 at A.M 

 at P.M. 

 at P.M. 

 at P. M. 

 at A. M. 



The principal objcftion to Mr. Edgeworth's machine is, 

 that it would be of a vaft fize, and each pointer would require 

 a man to work it. He defcribes, at the end of his paper, 

 a portable machine, which is made of fpars and poles jointed 

 together, and braced by cords. We think the fecond kind 

 of French telegraph, which was fet up between Landau 

 and Paris, would anfwer the purpofe very well : it has five 

 indicators, and the movements are made by machinery in the 

 houfe below. 



Major C. Le Hardy, in the Tranfatftions of the Society 

 of Arts for 1808, vol. xxvi. has defcribed a telegraph which 

 is well adapted for exhibiting fignals which fliall indicate 

 numbers. It has four indices or pointers, each confifting of 



a long arm, carrying a fquare index-board or pointer at the 

 extremity. One of thefe pointers reprefents units ; the 

 fecond, tens ; the third, hundreds ; and the fourth, thou- 

 fands. All the four indices move on a common centre by 

 the machinery ; and to diftinguiih them one from another, 

 each board is placed at a different diftance from the centre, 

 of motion, fo that in their motion they defcribe four circles 

 of different radii. The pofition of the arm, with refped to 

 the horizon, is made to iiKlicate the numbir which is to be 

 exprcffed by each index refpeftively, and there arc ten dif- 

 ferent poClionsfor each, anfwering to the numeral charaflers. 

 To identify thefe ten pofitions, a large frainc is fixed dole 

 behind the pointers, parallel to tiic plane of their motion ; 

 • .-.nd 



