10 Implements of Hufbandriu — Tzcc-Furrmv- Ploughs,

of the cattle, but is equally advantageous in increafing the ftrength of the iin-pleinent.

It is ftill further remarked, that this fort of plough has lately been found ufeful inhis own country, in even breaking up ley-ground, although formerly only in com-mon ufe for fallowing, not being thought capable of ploughing leys, as, from theirconftruftion, requiring too great ftrength in the team ; and that a premium has latelybeen given for this fort of plough, working ley-ground only. He ftates alfo, that oneacre and an half of ley-ground was broken up by four oxen with great eafe to them-felves in three hours and fifty-five minutes, they having, as part of a conftant courfeof work, ploughed feventeen perches fhort of an acre of the fame kind of groundthe fame morning: this was performed in order, he fays, to prove the■ effect offmoveable plates at the extremities off the mould-board, that the furrows might be.laid more or lefs flat; as mould-boards formed to lay furrows in ley, fo as to give th.e :greateft quantity of mould or foil to harrows, cannot be of that fliape or form belt fuitedto make good work in ftirring earths,more efpecially the laft,which ought tobe thrown:up in fina.ll feains, as it were, that the feed may be properly buried. For this purpofe.it has, he aflerts, hitherto been ufual to rip off the plate and drive in wedges, bywhich the mould-plate muft be liable to be injured ; and from the trouble attendingthe operation, it has often been omitted, and confequently the land imperfeftlyworked. This inconvenience may, he fays, be remedied, and the mould-board be.adjufled with great facility and expedition, by having the neceffary parts of themould-board or plate cut off, and afterwards connedted with the fixed parts of it bymeans of flat hinges, or of thin flexible plates of tempered fteel, or of hard ham-,mered iron, fo as to admit of thefe parts being fet to have different inclinations;with the fixed part of the mould-board. By means of two ferews pafling from the.infide through the lower parts of the handle of the plough, oppofite the back parts,of thefe moveable pieces, they may be kept at any defired degree of inclination ac--cording to the nature of the work to be performed. As ley-grounds cannot be laidtoo flat, or feed earths too much on an edge, by this improvement in the mould-,board of thefe ploughs he thinks it may be readily adjufled for either purpofe, as it.may be rendered more flat or more convex, according to the circumftances of the cafe.That part of the mould-plate the moft liable to wear fhould be made of double thethicknefs of the others, in order to render it as durable as the reft of the plough.

The increafed weight of draught when thefe moveable plates were extended,did not appear, he obferves, on trial, in a two-furrow-plough, to be, by the cops,more than twelve pounds, in. ley-ground at fix inches depth. The fridtion in fur-.