C6 ANNUAL OF SCIENTIFIC DISCOVERY. 



are watching and that point. A little trap-door the month of the appara- 

 tus is instantly shut, a cock is turned, the air-pump below begins to suck, 

 and in a few seconds you hear a soft thud u_-;>.h:st vhe end of the tube; the 

 little door is opened, and a cylinder of gutta-percha, encased in flannel, about 

 four inches long, which tits the tube, but loosely, is immediately ejected upon 

 the counter; the cylinder is opened at one end, and there we find the de-- 

 patch. 



"Xow it is quite clear that it is only necessary to enlarge the tubes and 

 to employ more powerful engines and air-pumps in order to convey a thou- 

 sand letters and despatches, book parcels, etc., in the same manner. And 

 this the company are forthwith about to do. At the present moment the 

 contract rate at which the mail-carts go is eight miles per hour. The Pneu- 

 matic Company can convey messages at the rate of thirty miles an hour, and 

 this speed can be doubled if necessary. 



"The company arc also about to lay down a pipe between the Dock and 

 the Exchange, for the conveyance of samples of merchandise, thus practi- 

 cally bringing the Isle of Dogs into Cornhill ; and for all we know this in- 

 vention may hereafter be destined to relieve the gorged streets of the metrop- 

 olis of some of its heavy traffic. 



" At the station of the International Telegraph Company, in Telegraph 

 Street, the pipes wind about from room to room, sufficient curve being main- 

 tained in them for the passage of the little travelling cylinder which contains 

 the message, and small packages and written communications traverse al- 

 most as quickly in all directions as does the human voice in gutta-percha 

 tubing, to which in fact it is the appropriate addendum." 



THE CLEARING OF DRAINS AND WATER-COURSES. 



Messrs. Easton & Amos, of London, have patented a curious method of 

 adopting to some convenient part of a drain, sewer, or water-course, a grat- 

 ing, of peculiar construction, whereby any extraneous solid matters, such as 

 weeds, pieces of wood, brickbats, stones, the dead bodies of animals, or other 

 substances, may be arrested in their progress, and removed, so as to prevent 

 them from blocking up the water-course and stopping the flow of the water. 

 To this end a chamber or recess is constructed at some convenient part of the 

 drain, sewer, or water-course, and made to extend across it from side to side. 

 In this chamber is mounted a movable grating in such a manner as to 

 extend transversely across the whole of the water-way. The grating is to 

 be formed of a suitable number of endless chains, connected together later- 

 ally in any convenient manner, and provided with projecting pins, points, or 

 hooks. Or a number of short bars, similarly provided with projecting pins, 

 may be jointed together in an endless series, so as- to form an endless grat- 

 ing, which is to be passed round wheels or rollers mounted in the chamber 

 or recess. This endless chain or grating should not be placed vertically, but 

 at an inclination to the line of the drain or sewer. It will be understood that 

 the water and liquid matters will pass freely through the endless chain or 

 grating, but that solid matters of any great size or dimensions, or that would 

 be likely to cause an obstruction in the water-course, will be arrested by the 

 grating, and by causing the same to rotate (by communicating motion to the 

 wheels or rollers on which the endless chahi or grating is mounted), the pins, 

 points, or hooks attached to the grating will be caused to lift up siu-h solid 

 matters out of the chamber formed in the drain, and deposit them in. some 

 receptacle provided above for that purpose. 



