The scales of commerce and trade: ballancing betwixt the buyer and seller, artificer and manufacture, debitor and creditor, the most general questions, artificiall rules, and usefull conclusions incident to traffique: comprehended in two books. The first states the ponderates to equity and custome, all usuall rules, legall bargains and contracts, in wholesale ot [sic] retaile, with factorage, returnes, and exchanges of forraign coyn, of interest-money, both simple and compounded, with solutions from naturall and artificiall arithmetick. The second book treats of geometricall problems and arithmeticall solutions, in dimensions of lines, superficies and bodies, both solid and concave, viz. land, wainscot, hangings, board, timber, stone, gaging of casks, military propositions, merchants accounts by debitor and creditor; architectonice, or the art of building. / By Thomas Willsford Gent.

An Explanation in Gain or Loss with time un∣known. Lib. 2. Parag. 10.

A Tradesman bought Nut∣megs 〈 math 〉〈 math 〉 at 8 ss the l, and sold them all again at 9 ss the l, what day of payment must he allow, whereby to gain af∣ter the rate of 20 l per cent. per ann. in all such like Cases, as 100 l to 12 Moneths, so 20 l. secondly, as 8 ss the price, unto 1 ss the gain made: the first rule is reverst, the other direct: in the third row of the Table stand the products, and under that again (in the fourth Table) is plac't the opera∣tion in a reverst proportion, but may be made direct if you please: the answer to the question here in this, is 7 Moneths and 15 dayes, the time of payment; which makes the gains proportionable unto 20 l per cent. per annum, the thing required: had the Proposition been of losse, the operation is the same, so it needs no example but this.