122

MANUFACTURES.

Maniifac- the impelled point of an engine but at present, without' inquiring into the nature of the engine itself, or of thework it is intended to perforin. A wind-mill, for exam-tion of pie, is the same in its principle whether it is intended to

mills. pump water or grind corn, so likewise a water-mill may

be converted to the purposes of boring, sawing, rolling,grinding, [&c. ; a horse-mill, also, as far as its powerextends, may be employed for any of the above pur-poses ; and so, also, may the steam-engine. It will,therefore, be understood, that the term mill, as used inthis chapter, implies only such a form of Machinery ,as will enable the five principal classes of first moversto produce rotation ; this rotation once produced, itmay be applied of course to the impelling of anyengine, or to any manufacturing processes to which itspower is competent.

Under this arrangement we have to describe thehand-mill, tread-mill, horse and cattle-mill, wind-mill,and water-mill; and the

Steam-engine, which is also but a mill, according tothis acceptation of the term, will be treated of in thefollowing chapter.

(81.) Hand-mill .—It is probable that this is a Machineof the highest antiquity. We can scarcely conceive astate of civilized society in which some process was nothad recourse to, to prepare corn for the formation ofbread, and there can be little doubt, whatever may havebeen the date of the invention of horse-mills, or of windand water-mills, that they were preceded by hand-mills.When the World was but thinly peopled, and everyfamily formed almost a distinct community, there wasno call for a greater power than what might be fur-nished by one or two persons working at a mill ; and,accordingly, this see„is to have been the means adoptedeven so late as the time of Christ, who says, Matthew ,ch. xxiv. ver. 41. “ Two women shall be grinding atthe mill, the one shall be taken and the other left.” Aspopulation and civilization proceeded, and the advan-tage of division of labour began to be in some measureunderstood, it was found desirable that the reduction ofcorn to flour, (which was doubtless the first intention ofthe mill,) should be attended to by certain persons for ageneral supply to the community, and then horse-mills,or cattle-mills, were constructed; and even to this dayin the East, mills of this description are nearly theonly ones employed. A recent fire at Constantinople which destroyed more than 1500 houses, burned downalso 120 horse-mills; a proof of the very little advancewhich has to this day been made in the progress of theArts in that ill-fated Country. The water-mill is sup-posed to be of Greek invention, but the inventors of thatuseful Machine, the wind-mill, are not known. Wind-mills are, by Montucla , supposed to have been used bythe Dutch in the VUIth or IXth Century, but othershave imagined that the idea of their construction wasderived from Asia in or about the Xllth Century.

Our business, at present, is to describe the hand-mill,which although wholly superseded in its application togrinding flour, except in very particular cases, is stilluseful for some purposes where great, power or great sup-ply is not wanted, as for grinding malt in families, andfor some other domestic purposes. It has been also tilllately, and is perhaps at present, employed in some pri-sons for furnishing a means of prison labour; these,however, are now greatly if not entirely superseded bythe much more conveniant and appropriate engine thetread-mill.

Various forms of hand-mills have been devised, of which Machinery ,a remarkable one is described in Gregory’s Mechanics ; in -v—which the crank is worked by a rowing motion, the mostadvantageous way of applying a man s strength. It isan old idea , being described in Bockler’s Theatrum Ma-chinarum. This contrivance seems only to require afly wheel to make it a complete Machine.

(82.) A very simple hand-mill is represented in Simpleplate v. fig. 1, which requires but little description. AB hand-mill,is a strong wooden frame ; W a face wheel running inproper bearings at P P. This wheel is turned by thewinch E; the teeth of the wheel W engages with thestaves of the trundle on lantern T, and on the spindleof this is fixed the revolving or upper stone of the mill,not seen in the figure, the stones being enclosed in thecase C. The corn is first placed in the hopper H, whenceit passes to the stones, and being ground is carried outat the spout D.

Hand-mills are employed in various processes for do-mestic purposes, and by retail tradesmen for grindingcoffee and malt, pulverizing sugar, and for many otheruses; but their constructions are generally so simpleand so well known, as scarcely to require notice in thisplace. Some other hand-mills, or Machines of equivalentaction, will be explained in subsequent sections in de-scribing different mechanical and manufacturing pro-cesses, and in particular we refer to Rustal’s hand-millfor grinding and dressing corn, under the section Corn-mill.

(83.) Tread-mill .—This is a new and very useful Tread-mill.invention, for which we are indebted to Mr. W. Cubit,

Civil Engineer . Its utility, however, depends ratherupon the purposes to which it is applied than to anyintrinsic value it possesses as a mechanical construc-tion. We have seen (§ 12.) that it is impossibleto apply human strength as a first mover of Machinery without a great pecuniary sacrifice; consequently, wemust not look to the Tread-mill as an economicalmode of obtaining mechanical power, as far as ex-pense is considered; but there is a higher order ofeconomy, which is (if we are not much mistaken) ad-ministered to by this application, viz. the correction andimpiovement of the morals of the idle, vicious, and dis-ordeily part of the community. Many of this class ofpersons are so debased and degraded by the courses, oflife they have led, that they would prefer, perhaps, thedreary abode of a prison in idleness to that of living bythe sweat of their bro.w, and to such dispositions nothingcan act as abetter corrective than the Tread-mill. Herethey must work , no shifting or contriving will allow themto lie by and throw their share of labour upon their morewilling companions in misery ; and it is accordinglyfound by the reports of the Governors of various prisonsin which this uncompromising Machine has beenerected, that few who have had a full trial of thislabour are willing to expose themselves to it a secondtime. If they must work when in prison, they, of course,had better work out of it, and this appears to have beenthe actual result in many cases. See A Report of theSociety for the Improvement of Prison Discipline, 1823.

The usual form of the Machine is a long wheel,varying from eight or ten feet to twenty or more feet inlength ; and a number of these are sometimes united bycouplings to a very great length ; the usual diameter isabout five feet or about sixteen feet in circumference,furnished with twenty four leaves or steps, each ofcourse of eight inches, and within which, at a sufficient