1852.] 



CENTRIFUGAL POWER, Ac. 



double and securely framed to them and braced, as shown to form 

 the apron. Three inch sheet piling was then driven above and 

 below the dam and securely spiked to the outside longitudinal tim- 

 bers, and continued well into the bank so as to prevent the water 

 penetrating and destroying the foundation ; coarse gravel and clay 

 ^vas closely packed among the foundation timbere and well ram- 

 med. The whole apron was also filled with the same material, 

 and covered with five-inch plank, secured with trenails and spikes. 

 The piers being planked inside and out are — in the absence of stone, 

 which could not be conveniently procured — filled to the top vnth. 

 coarse grarel intei-mixed with clay ; cross ties being inserted at 

 intervals, dovetailed upon the posts to prevent the sides from 

 spreading. A puddle 

 ditch was made about 

 twenty feet into the 

 banks on each side 

 from the land piers, 

 and being well pud- 

 dled, secured the banks 

 from destruction in the 

 event of an extraordi- 

 nary rise of water 

 ovei-flowing them. 



The manner in 

 which the Bridge is 

 placed on the piei-s, is 

 made sufficiently evi- 

 dent from the draw- 

 ings, and the accom- 

 panying estimate of the 

 quantity of material necessary to complete the structure, will afford 

 sufficient data from which to estimate its cost. It was deemed 

 advisable when building this dam to avoid using any but the most 

 simple plan for hoisting the sluice boards ; at the same time, it is 

 evident, that should it at any time be desirable to introduce a more 

 complete apparatus, any of the numerous contrivances for that 

 pui^pose may be readily adapted. 



It will be seen from the drawings that the outside jilanking of 

 the piei-8 was put on diagonally, in order to brace the framing, and 

 thus save the necessity of framing braces in the work. The whole 



Applications of Centrifugal Action to Manfacturing pur- 

 poses. — It is well known that a centrifugal machine has been 

 hitherto employed with much advantage for the drying of textile 

 fabrics and for clarifying sugar ; but these are not the only pur- 

 poses to which it is adapted ; for every day new applications of 

 this apparatus suggest themselves, and important problems are 

 solved by its means. We now learn that one of the most 

 important operations of bi'ewing may be wonderfully simplified 

 by the use of a centrifugal apparatus. It has been hitherto con- 

 sidered extremely difficult to reduce the temperature of beer to 

 the degree of coolness requisite ; it has been necessary to make 

 use of refrigeratora for this purpose, and, notwithstanding all 

 precautions, mistakes not unfrequently happen. It occurred to 

 some English brewer's that this difficult cooling process might be 

 effected by means of a centrifugal machine. This idea has been 

 put in practice with complete success. The beer was reduced to 

 the desired temperature by merely passing it through the machine ; 

 and this was effected not only with great rapidity, but also with 

 considerable economy. Some time back, M. Touche, of Paris, 

 endeavoured to produce ice by means of a hydrofugal apparatus. 

 He did not succeed in reducing water to the freezing point, but 

 he cooled it to a degree far below that requhed in brewing beer. 

 It would be superfluous to explain these results, for every one is 

 acquainted with the effects of a very rapid ventilation, and the 

 centrifugal machines are made to rotate at the rate of 3000 

 revolutions per minute, and even quicker. We are further in- 



of the planks were put on with If inch oak trenails, the butts only 

 being spiked. 



In some cases where large stone can be conveniently obtained it 

 may be cheaper to build a Dam of this kind without piHng. 

 Where this occui-s the piles may be dispensed with, and the tim- 

 ber merely bedded in the bottom of the creek ; the piers and 

 apron being well packed with stone will serve to keep the dam 

 firm : there should then, however, be a pier in the middle of the 

 length of the dam, instead of the framing shown in the drawing, 

 in order to keep down that part of the foundation. Since in creeks 

 liable to heavy freshets, and where the water sometimes hacM up 



below the dam to a 

 considerable height,the 

 whole structui-e being 

 timber, becomes so 

 buoyant that it is in 

 danger of floating 

 away, hence the ob- 

 ject of the piling was 

 more to prevent the 

 foundation from rising 

 than to support the 

 weight of the super- 

 structure, which object 

 would of coui-se be 

 effected by the addi- 

 tion of sufficient stone 

 as before stated. 



The following is the estimate of material for the Dam and 

 Bridge : — 



Round piles of hardwood 12 inches diameter, hneal feet, 1680 

 Square do. pinewood 12 do. do. do. 660 



3 inch sheet piling, board measure, superficial feet, - - 5250 



Oak and elm squared timber, cubic feet, 3500 



Pine do, do. do. do, 3450 



3 inch pine plank, board measure, superficial feet - - 42300 

 5 inch oak and elm do, do, - - - 12000 



Wrought iron, in lbs., - - - 1740 



Wrought spikes, in lbs., -.- goo 



fornied that in certain manufactories in Alsace a hydrofugal 

 machine is used for making starch. When the flour is stirred 

 about in water, the diflerent substances range themselves accord- 

 ing to their specific gravities, unless prevented by some peculiar 

 circumstances. Now, this is precisely the result obtained by the 

 centrifugal machine ; starch, being the heaviest substance, separates 

 itself from the othei's, and is first precipitated. The centrifugal 

 machine may also be advantageously applied for classifying grain, 

 seed or ore?, according to their respective densities, whether hquid 

 or sohd, provided they are not of a cohesive nature, or that 

 whatever cohesiveness they possess may be easily removed. In 

 fact, the centrifugal appai-atus may be applied to so many differ- 

 ent manufactures, that it may be justly looked upon as one of the 

 most fortunate and fruitful inventions of modern times. — Moniieur 

 Industriel, 



Syphon Filter. — The Syphon Filter is, perhaps, the most 

 convenient kind for general purposes, as it may be readity carried 

 about and used by any ordinarily available pressure. The shape 

 of the filter is that of an elongated bell. It is made of wliite 

 metal ; and, at the top of the beU-sliaped vase, there is inserted 

 an inflexible metal tube, furnished with a stop-cock near the end. 

 The vase is filled with powdered quartz, of various degrees of 

 fineness, and the mouth of it is closed with a perforated cover. 

 When required to be used, the vase is inverted in the water to be 

 filtered, and the tube is allowed to hang below it. Wlien the air 



