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calculation, it was only about eleven grains to a 

 foot; which is quite fufiicient, if the feed be good, 

 and it be not deftroyed by vermin. 



Now with regard to the quantity of land this 

 drill-plough may fovv. If a horfe walks at the rate 

 of two miles per hour, he goes fixteen miles in 

 eight hours, or 28,460 yards. As he fows two 

 ridges at once, this is feven lengths and two- 

 thirds per acre, or 1686 yards to fow an acre, be- 

 ing nearly feventeen acres in a day. 



Four horfe-hocings are calculated equal to two 

 ploughings. In plain ploughing they fuppofe the 

 ridge is ploughed with four furrows, or eight for 

 twice ploughing. The four horfe-hoeings are eight 

 furrows, equal to two ploughings. 



Mr. Tvll directs four hoeings, and Mr. 

 Forbes five. 



Firft. In November, when the plant has four 

 blades. 



idly. In March, deep, and nearer the rows 

 than the former. Both theft hoeings fhould be 

 from the rows. 



2dly. Hand- 



