THRESHING-MACHINE. 



And it is added, that, aboiit twenty years after this, a 

 third attempt was made by a Mr. Eldcrton, near Alnwick, 

 and a Mr. Smart, at Wark, both nearly about the fame time. 

 Their machines were fo conUriiacd as to ad by rubbing, m 

 place of beating out the grain. The Iheaves were carried 

 between an indented drum, about fix feet in diameter, and a 

 number of rollers of tlie fame defcription ranged round the 

 drum, towards which they were prelTed by fprings, in fuch 

 a way as to rub out the grain when the drum was turned 

 round. Upon trial, this method of conftruAion in thefe 

 machines was alfo found defeftivc, as along with its doing 

 very little work in a given time, it bruifed the grain, and fo 

 materially hurt its appearance, as to Icffen its value confider- 

 ably in the markets. 



It is furtlier ftated that the machine, in its then imperfeft 

 Hate, was fccn by the late fir Francis Kinloch, bart. of 

 Glimcrton, a gentleman well acquainted with mechanics, 

 and who had paid much attention to country affairs : it 

 occurred to him, that the machine might be rendered more 

 pcrfeA, by inclofing the drum in a fluted cover, and fixing 

 on the outfidc of it four fluted pieces of wood, capable of 

 being raifed a little from the circumference by fprings, in 

 fuch a way as to prefs jgainft the fluted cover, and to rub 

 out the grain as the (heaves paffed between them ; but after 

 repeated trials, it was likcwife found to bruife the grain 

 nearly as much as the model from which it was copied. In 

 that Hate it remained for fomc time, and was afterwards fent 

 by fir Francis to a very worthy and ingenious charafter, 

 Mr. Micklc of Know-Mill, in his neighbourhood, (a mill- 

 wright by profefTion,) who had for a confiderable time em- 

 ployed his thonghts upon the fame fubjeft. After much 

 confidcration, and feveral trials, it appeared to Mr. Mickle, 

 that the purpofe of feparating the grain from the ftraw 

 might be accompliflicd upon a principle different from any 

 that had hitherto been attempted, namely, by llcutches ail- 

 ing upon the fheaves by their velocity, and beating out the 

 grain, in place of prefling or rubbing it out. Accordingly 

 a model was conftrudled at Know-Mill, in which the grain 

 was beat out by the drum, to which it was prefented through 

 two plain feeding rollers, which were afterwards altered for 

 fluted ones. The firft machine, on a large fcale, executed upon 

 this principle, was, it is faid, done by a fon of Mr. Mickle's, 

 for a Mr. Stein of Kilbagie, in the year 1786, which, 

 when finilhed, performed the work to the fatisfaftion of all 

 parties. A patent was afterwards apphed for and obtained 

 in 1788. Since that period, as well as the firft introduftion 

 of thefe machines, many other improvements have been made 

 on them by different ingenious artificers in many different 

 places ; a fcrcen has been added for the grain to pafs through 

 into a winnowing machine, and a circular rake to remove 

 the draw from it ; as before this addition, the ilraw was 

 forced out from the beater upon the upper barn-floor, and 

 required much time and labour in (haking and putting it into 

 order, which by this contrivance is faved. And befidss hav- 

 ing a fuflTicient degree of velocity, without its being fo great 

 as to injure the machinery, it is found that a point upon 

 which the clean threfhing of all forts of grain materially de- 

 pends in the ufe of this machine, is the management of 

 the ij-on covering, under which the beating-wheel, having 

 fix of' more beaters, moves : in fome machines this is fixed, 

 v/hilc the beating-wheel is capable of being raifed or de- 

 preffed at pleafure ; but a more late improvement is to 

 fender the iron roof moveable and the wheel fixed, the i^on 

 bcmg placed foclofe to the beaters, that the grain is rubbed 

 as well as (haken out of the car. And in fomc cafes the 

 beaters arc fomewhat rounded, but the flat form is probably 

 t)etlcr. I J 



Different machines of this fort are alfo faid to have been 

 lately conftruAed fo as to work with chains inftead of cogs, 

 and to perform the bufinefs in a fatisfaftory manner. 

 Another great improvement is likewifc believed to have 

 been made on the feeding rollers ; which is that of having 

 the upper roller, inftead of being one folid cylinder of wood, 

 with rods of iron fixed upon it, as was formerly the cafe, an 

 oftagon or decagon of caft iron, and divided into four parts, 

 which are loofely joined into each other, fo that in turning 

 round, each part can rife or fall in a feparate manner, accord- 

 ing as the corn is fpread out ia a thicker or thinner way. 

 The advantage is, that by means of this contrivance the corn 

 is regularly held ; whereas, by the roller being all of one 

 piece, if at one part the grain fhould happen to be more in a 

 heap or lump than at another, the whole roller is raifed, and 

 a great part of the grain paffes through, without having been 

 held fufficiently to the beaters, and is confequently imper- 

 feftly thrcfhed out. 



This fort of machine is fometimes conftrufted with a 

 vertical Ihaft, on which is fixed in a horizontal manner an 

 iron bevil wheel, fix feet in diameter, which drives another 

 about eighteen inches diameter upon a tumbling ffiaft, upon 

 which is alfo an iron fpur-wheel, three feet fix inches ia 

 diameter, driving one about ten inches upon a fliort iron 

 (haft, which likewife carries a drum or pulley, three feet fix 

 inches in diameter, from which a fix-inch ftrap drives one 

 nine or ten inches in diameter, hung upon the iron fliaft or 

 fpindle which runs quite through the wood-beater or barrel, 

 two feet in diameter, and three feet in length, having fixed 

 upon it, by means of ftrong fcrews into its iron bonds, 

 twelve wrought-iron bars, about an inch fquare, which 

 beater making upon its horizontal axis about three hundred 

 revolutions in a minute, and confequently nearly three thou- 

 fand fix hundred ftrokes in that fpace of time ; the corn 

 being carried to it by means of a cloth, which is moved 

 forwards by rollers, lying nearly upon a flat furface of fix 

 feet long, by three feet wide, two to three feet high from 

 the ground-floor, which is a very convenient pdfition to feed 

 upon, and palling between a pair of fluted rollers, over a 

 bar, comes in contact with the beater, through a cavity, 

 which may be varied by fcrews, from an inch in width, to 

 the thicknefs of a grain of corn, when the ftraw is imme- 

 diately delivered, perfectly clean upon the floor on the out- 

 fide of the machine, no more injured for thatch, or other 

 purpofes, than by the flail, and the corn in its paffage under 

 the beater is filtered through a wooden frame to the floor, 

 where it remains for removal. Upon this kind of threfhing- 

 machine many different trials have been made in the view 

 of afcertaining what fort of power, conilruftion, and velo- 

 city or fpeed, would produce the bell and moft beneficial 

 effects on the work, and many improvements have been 

 fuggefted which we have not room for reciting. 



Some machines of this fort have large wooden fly-wheels, 

 of from twelve to fifteen feet diameter, fixed upon the 

 tumbling-fliafts, which run over or above the horfe's heads, 

 perhaps made of fir-timber, as cork unfortunately is feldom 

 to be met with ; but as their fpeed, in fuch a fituation, can 

 rarely afford any affiftancc, the lighter they are, the lefs 

 impediment, it is fuppofed, they wiU produce. The bars or 

 beaters are alfo fometimes as much as an inch and a half, or 

 two inches thick, from the barrel or roller upon which they 

 are fixed, and the roller itfelf three feet or more in diameter; 

 but fo much of the bar is certainly, it is thought, unneceffary, 

 as exceeds the length of ftraw drawn in by the rollers, 

 during each interval between the ftrokes, and which is 

 feldom more than half an inch ; confequently, whatever is 

 more than three quarters, produces an increafed impedi- 

 ment. 



