The schoolmaster's most useful companion, and scholar's best instructor, in the knowledge of arithmetic [electronic resource] : In two parts, viz. Part I. Containing the first principles of arithmetic with plain and concise directions to work the following rules, viz. addition, subtraction, multiplication, division, reduction, the rules of three, interest, alligation, fellowship or partnership, rebate, progression, vulgar and decimal fractions, extraction and use of the square and cube Roots. With a variety of practical questions to exercise all the foregoing rules, each having the answer insersed, in order to save the master or tutor a great deal of time and labour, and help the scholar forward in his progress in the practical part of arithmetic. Part II. A very short and easy sketch of book keeping, by way of common debtor and creditor only; by which accompts may be kept with great ease and exactness. To which is added, an Appendix. Containing rules for the true performing of cross multiplication with the application to actual practice in measuring carpenters, joiners, paviors, thatchers and bricklayers work; as also how to gauge coolers, cisterns, and ca[s]ks in wine, ale gallons, and malt bushels, both by the pen and sliding rule. The whole digested in such a manner as to render it not only useful in almost every branch of life and business, but very entertaining. The second edition, corrected, improved, and recommended by several masters and others, for the use of schools, &c. By D. Fenning, Author of the Young man's book of knowledge; New treatise on the use of the globes; New and complete spelling dictionary; Universal spelling book; and Royal English dictionary, published by the King's authority.