_Resp._ It has been used with very great Success for these several Years last past, but never like to be common, unless it be described in a more geometrical Manner, than any Plough has hitherto been; for the Plough-wrights find it difficult enough to make a common Plough with one Coulter to perform as it ought, for want of the necessary Rules of their Art. It is upon this Account that the Two-coulter’d Ploughs are used in few Places, though they have been found of excellent Use, and have been formerly common: But, alas! when the Makers, who by their diligent Study and much Practice had attained the Perfection of their Art, died for want of learning to write their Rules mathematically, and shew how the mechanical Powers were applicable to them, the Art was in a Manner lost, at the Death of those Artists; and then the unskilful Plough-wrights, destitute of the true Rules, were not able to make a Two-coulter’d Plough to perform well, and then it was left off. Very lately ’tis revived, since the Three and Four-coulter’d ones have been used; from whence some have made a Shift to take the Rules of placing Two Coulters into a Plough, and they begin to be common again; and, no doubt, will cease again as soon as the Rules are forgot. [Illustration: _Page 291_ _Plate. I._ _B.Cole. Delin. et Sculp._] ’Tis strange that no Author should have written fully of the Fabric of Ploughs! Men of the greatest Learning have spent their Time in contriving Instruments to measure the immense Distance of the Stars, and in finding out the Dimensions, and even Weight, of the Planets: They think it more eligible to study the Art of plowing the Sea with Ships, than of tilling the Land with Ploughs; they bestow the utmost of their Skill, learnedly, to pervert the natural Use of all the Elements for Destruction of their own Species, by the bloody Art of War. Some waste their whole Lives in studying how to arm Death with new Engines of Horror, and inventing an infinite Variety of Slaughter; but think it beneath Men of Learning (who only are capable of doing it) to employ their learned Labours in the Invention of new (or even improving the old) Instruments for increasing of Bread. The easiest Method of perpetuating the Use of the many coulter’d Ploughs, and other newly-invented Instruments of Husbandry, is by Models, _i. e._ the Things themselves in little; and these may be all portable even in a Man’s Pocket: Every Part must be fully described, with the true Dimensions, and the mathematical Reasons, on which their Contrivance is founded. Directions also for using them must be given at the same time that their Manner of making is described. In some, the very Horses which draw must be represented, to shew the manner of fixing the Horses, and the Traces: Cautions against all the Errors that may happen by the want of Experience in the Makers or Users, must be given.