FILE. 



FILTER; FILTRATION. 



78 



French exhibit such a beautiful uniformity of delineation when 

 examined with a magnifier, that no doubt seems to be entertained by 

 many persons conversant with the art of their being cut by machinery 

 of some sort. But although the French are so successful in the pro- 

 duction of this exquisitely delicate cutting, they are not equally so in 

 the execution of the rougher sorts ; and, consequently, English files 

 are in high reputation in Paris, whither large quantities are regularly 

 transmitted. As an example of minute but useless work, we may 

 adduce the Danish file sent to the Great Exhibition in 1851. It was 

 four-square, and weighed 10 Ibs. ; the file-cuts on the surface repre- 

 sented the royal arms, and views of several public buildings in Copen- 

 hagen. It was hollow, and contained a nest of ten files, one within 

 another, the innermost being little more than an inch in length. Still 

 more pretentious was a file made by Hiram Younge, a file-cutter in the 

 employ of Messrs. Carr of Sheffield; it was 54 inches in length, and 

 was covered all over with landscapes, emblems, symbols, inscriptions, 

 foliage, and other devices, all produced by chisel-cuts of different 

 length* and depths. 



A brief notice of three among the many machines invented within 

 the last few years will illustrate the modes in which the cutting-action 

 is brought about, and will also show that there are really machine-cut 

 files now made in England. In 1856, a file-cutting machine, invented 

 by Mr. Ross, was adopted in Messrs. Hetherington's works at Glasgow ; 

 and by the spring of the next year, five others had been added. The 

 chief difficulty hitherto has been in the attainment of a proper 

 modification of blow, so as to suit various qualities of steel, widths 

 of file, and depths of cutting ; and also to accommodate the blow to 

 any irregularities of surface. These difficulties Mr. Ross has sought 

 to remove, by an ingenious but very complex arrangement of mechanism 

 calculated to produce files of a medium degree of size and fineness. 

 In Messrs. Preston and Macgregor's machine, patented in 1858, there 

 is a shaft turned by a strap in the usual way ; conical cams, fixed on 

 the shaft, raise and lower a hammer-head and spindle ; there are fixed 

 guides on the anvil block ; the upper swage is fixed at the lower end 

 of the spindle, and the lower swage between the guides ; and thus 

 the blows of the hammer are brought down vertically. The lift of 

 the hammer is varied by varying the distance between the cams on 

 the shaft. There is a chisel-holder with a ball-joint, and a spring for 

 retaining the holder in its place. There is a compensating move- 

 ment for regulating the force of the blow. The file-blank is placed 

 in .a recess in the anvil. Messrs. Greenwood and Batley set up at 

 . in 1859, a file-cutting machine of French invention. The file, 

 arrangement, its placed in a self-adjusting bed, capable of turn- 

 ing in any direction ; the chisel is fixed in a vertical slide, put in 

 n by a spring and cam and gives about a thousand blows in a 

 minute. It is said to do about as much work as ten skilful file- 

 cutters. This form of machine is also in operation in France and 



III!. 



I are among the articles which exemplify the importance of 

 trade-marks. A innk was granted many years ago by the Sheffield 

 corporation to Daniel }>raiiiinall, to be stamped on his files ; and so 



t int was this in a commercial point of view, that on one occasion 

 Brammall obtained 2'HMU. damages against a rival manufacturer, for 

 an infringement of the mark. This matter was adverted to by one 



jurors of the Paris Exhibition in 1855, in connection with 

 the file-manufacture : " The fundamental obstacle to the growth of 



ranch of industry results from the custom adopted by almost all 

 manufacturers of placing false marks on their produce. This deplor- 

 able custom is due in part to the desire that unconscientious manu- 

 facturers, convinced of their real inferiority, have to turn to their 

 own profit the resources of the best foreign manufacturers, acquired 

 by a long career of honesty and talent ; it is encouraged by the retail 

 dealers, who wish to keep manufacturers dependent on them, and to 



r the consumer from knowing the real marks of steel goods. 

 Manufacturers, short of capital, submit in this matter to the terms 

 dictated to them by the dealers, renounce their individuality, and 

 stamp upon then* goods such marks as the buyer chooses to order, and 

 even to substitute the name of the retail dealer for their own. The 

 history of 1 1 -teel trade proves that a skilful manufacturer, 



who consecrates liis life to found the reputation of the trade-mark he 

 has chosen, can leave in the sole possession of that mark a large 

 fortune to his descendants. The government would, therefore, render 

 skilful and conscientious manufacturers (the only ones that ought to 

 be encouraged) an immense service in imposing upon each producer 

 the obligation to place hix own mark upon his manufactures." It is 



iile that this mention of government interference wan due to a 

 Frenchman, with whom snch a mode of settling trade difficulties is 

 familiar. In reference to the file-manufacture, the chief piracies occur 

 in Germany, where English trade-marks are copied with unblushing 



rtery. 



FILE, is a line of soldiers one behind the other. The term is com- 

 monly used also to designate a front and rear rank man together ; or 

 aa in the exprc.-'sinn HO many rank and file, when it means so many 



n who are nut <>nii/i'i> <>r sergeants. 



FM.K MAKCHINfl, iit where a line of soldiers, either in single or 

 double rank, facing to the right or left, -march in that direction ; each 



.ind rear rank man then compose a file. 

 FILIATION, ORDER OF. [BASTARDY.] 



FILLET, a flat rectangular moulding, of very frequent occurrence in 

 architecture. It is used to terminate or divide other mouldings, as in 

 the cavetto, which is surmounted with a fillet, and in the flutings of 

 columns, which are divided by a fillet. The fillet is much used in 

 entablatures. [COLUMN.] 



FILTER ; FILTRATION. Filters may be ranked as of four kinds : 

 those employed iu straining various chemical liquids ; those used for 

 filtering water in small quantities for household use ; those used on a 

 large scale by the water companies ; and those used on shipboard for 

 converting salt water into fresh. 



1. Chemical jiltei's. The smaller kinds are strainers used in chemical 

 operations for rendering fluids transparent by separating the suspended 

 impurities which make them turbid ; or for separating and washing 

 the precipitates resulting from chemical analysis. They are usually 

 made of unsized or blotting paper; and they are used either spread out 

 upon cloth stretched on a wooden frame, or folded and placed in 

 funnels, and having consequently the form of an inverted cone. They 

 are either single or double, according to the purposes to which they 

 are to be applied. [CHEMICAL ANALYSIS.] 



2. Household filers. Various forms of filter are employed for the 

 purpose of filtering water, either for drinking or culinary purposes. 

 These niters generally depend upon passing water through sand or 

 small pebbles and charcoal. It is well known that the Thames water, 

 though it contains but little saline matter in solution, is frequently 

 turbid, owing to mechanical admixture of earthy matter ; and these 

 earthy matters, in the Thames and other kinds of river water, it is the 

 purpose of filters to remove, so as to render the water, though not so 

 agreeable as spring-water for drinking on account of its flatness, yet 

 well adapted for other purposes. 



A considerable portion of the river-water of Paris is filtered in large 

 establishments where it is employed. The filters made use of are small 

 boxes, many in number, lined with lead, open at top, and having at 

 the bottom a layer of charcoal between two layers of sand. If the 

 water is foul, the upper layer of sand requires to be renewed daily. At 

 the H6tel Dieu the boxes are hermetically sealed, and the water is 

 forced through the filtering layers by artificial pressure. 



A very simple water-filter may be made of a common garden-pot, 

 or similar vessel, with a bottom pierced with holes. Fill the lower part 

 with round pebbles, then place a layer of smaller pebbles, then coarse 

 sand, and lastly a layer, three or four inches in depth, of well-made 

 pounded charcoal. The water, in percolating through these various 

 strata, loses nearly all its mechanical impurities. A still simpler filter 

 may be formed of a layer of sponge pressed between two perforated 

 (MM* 



Murray's Self-cleansing Domestic Tubular Filter is soldered to the 

 end of the service-pipe. The enlarged part of the pipe contains a 

 perforated tube with several folds of flannel and linen wrapped round 

 it. The smaller tap communicates only with the outer casing, so that 

 ii'iwatt-r can roach it that lias not passed through the filtering tube. 

 The larger tap communicates with the interior of the tube ; and by 

 allowing it to run, the filter will cleanse itself. Iu Bird's Hydrostatic 

 Syphon Water Purifier, the filtration is performed in two inverted 

 cones containing filtering media, situated in the cylinder. When used, 

 the instrument is immersed in the water to be filtered, and the pipe 

 uncoiled so as to hang with its stop-cock below the bottom of the 

 instrument. On drawing out the air from the pipe, it acts as a syphon, 

 and a stream of pure water flows. Foster's Pressure Filter, recom- 

 mended for use by the Sanitary Board of Liverpool, consists of a 

 porous stone, hollow in the inside, and contained in a metal jacket. 

 This apparatus, when screwed into the service-pipe, causes the water, 

 forced through the stone by the pressure of the main, to lose all its 

 pollutions, and come out pure and clear. There are two taps, one of 

 which draws the filtered water from the interior ,of the stone globe ; 

 the other the unfiltered from the exterior ; and the apparatus is so 

 arranged! that the drawing of the unfiltered water cleanses the stone 

 and increases its powers of filtration. 



Some of the filters recently made have for their object the main- 

 tenance of a uniform pressure of the fluid upon the filtering surface by 

 a self-acting contrivance, which admits the fluid from a reservoir just 

 as fast as it passes off through the filter. On a small scale this may be 

 done by inverting a bottle, filled with the liquid to be filtered, with its 

 open neck or mouth in the funnel or other vessel at the bottom of 

 which the filtering materials are placed ; so long as the fluid in the 

 funnel is above the level of the mouth of the bottle, no fluid will flow 

 from the bottle into the funnel, because no air can enter the bottle to 

 take its place ; but BO soon as, by the process of filtration, the fluid in 

 the funnel falls below the mouth of the bottle, air enters it, and con- 

 sequently liquid flows out into the funnel until it rises high enough 

 again to prevent the admission of air. In other cases, the admission of 

 fluid to the filter is regufated by a ball-cock or valve connected with a 

 float. In a few instances, hydrostatic or pneumatic pressure is em- 

 ployed to increase the rapidity of filtration, by closing the filtering 

 cylinder, and forcing the fluid into it, either by a force-pump or by a 

 pipe from an elevated cistern ; by producing pressure by air or steam 

 upon the surface of the fluid ; or by occasioning a partial vacuum 

 beneath the filter, in the vessel which receives the fluid after it has 

 passed through it. When such pressure is applied, the water or other 

 fluid is sometimes caused to ascend through the filtering materials, or 



