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rollers run horizontally thro' the middle of the beaters, or main cifterns; and, be- 

 ing lodged upon pivots in the further walls, pafs thro' two holes in the nearer, and 



by pins, in a frame dropped (from the upper beam, or timber, that 

 lies between the walls) parallel to the main column; being each fupplied with a 



niuve again 



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fett of coggs, to work in thofe of the main wheel : and, at proper diftances, within 

 the beaters, they are alfo furnifhed with three or four crofs arms, to the ends of which 

 are fixed twice fo many pyramidal and truncated veflels, open at both ends; to run 

 thro' and agitate the liquor the better. Each of thefe is of a moderate fize; and, if 

 bottomed, would hold between two and three quarts. 



The whole frame is moved with great eafe and celerity, by one horfe; for whofe 

 courfe, fufficient room is always left between the beaters, in the building of the 



works ; which 



occa 



(ions them to project beyond the angles of the deeper. 



With 



this machine you may beat more liquor, in half or three quarters of an hour, than 

 fix negroes can do in fix : fo that it fully anfwers the expence and labour ; and fre- 



quently brings a weakly and imperfect tincture, to grain, which could be hardly 



done without infinite labour, otherways. Your works now ready and fit for ufe, 

 you begin to manufacture your Indigo in the following manner, 





The plants are cut with rape-hooks, a few inches above the root: they are 



ftrata in the fteeper. 



then tied in loads ; carried to the works ; and laid 

 When this is pretty full, the weed is overlaid with boards, and thefe fupported by 

 props, from the beams that overlay the ciftern : thefe being well fettled, you put in 

 as much water as will cover the weed, and leave it toditreft, and ferment, until the 



greateft part of the pulp is extracted ; without letting the tender tops of the weed, 

 run to putrefaction, which would fpoil the whole. On this critical juncture 

 chiefly depends both the quantity and quality of you rlndigo ; and in the management 

 of this point alone, the judgment of the planter chiefly con fills: he muft be there- 

 fore very cautious and watchful to know it perfectly ; for if he draws off the water* 



but two hours too foon, he lofes the greateft part of the pulp; and if the fermenta- 

 tion runs but two hours too long, the whole is fpoiled. To avoid both inconvenw 



ences, you muft, when the fermentation rifes, frequently draw out a handful of the 



weed ; and when you find the tops grow very tender, and pale ; and obferve 



the ftronger leaves to 



change their colour to a lefs lively pale ; you may be fure 

 you are then at the proper point, and ought to draw off the liquor without delay. 

 But you foon learn to know this critical juncture, by the height of the fermentation, 

 and .grain of the tincture; of which you may frequently beat a little in a filver cup, 

 or a foop-plate, for that purpofe; tho' the other is, by far, the beft and fureft way, 

 until a perfon is well experienced in the courfe of the operation. 



The pulp being thus extracted, the vents are opened, and the tincture discharged 

 by the proper taps, into the beaters ; where it is agitated and worked up by two or 

 three negroes, each with a bucket fixed to the end of a pole, (or by a proper engine,) 



who continue this labour, until the dye begins to granulate, or float in little fio- 



cuIoe in the water; which feparation is greatly forwarded by a gradual addition of 



fome clear lime water. But a perfon muft cautioufly diftinguifh the different ftages 

 of this part of the operation alfo ; and carefully examine the appearance and colour of 

 the floculae, as the work advances: for the grain pafles gradually from a greeniuh to 

 a fine blue, which is the proper colour of theflocula?, when the liquor is fufficiently 

 worked ; too fmall a degree of agitation leaving the grain green and coarfe, while 

 too vigorous an action brings it to be almoft black. But the different ftages may be 

 eafily diftinguiflbed on examining a fmall quantity of the liquor in a fiiver cup, from 

 time to time, as the procefs advances; and a little experience will foon learn you to 

 know them as well by a finele drop upon your nail; fo that you may flop at 



a paler 



quite 



kuow mem as vvcji uy a nngie drop upon your nail; io that you may 11 

 any degree of height, and have your Indigo of a deep copperifh blue, or of a 

 colour, as you chufe : and when the liquor, in which the flocula? fwim, is 



clear, you may be fatisfied there is lime-water enough ; but this muft be very clean, 

 for otherways your Indigo will be very much fpeckled ; and not in too great a quan- 

 tity, which would make it too hard, and of a greyilh caft. The 



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