THE ESTIMATING AND COSTING OFFICES on overall weights, on indicated horse-power, on volumetric capacity, or on some other recognized unit of measurement. The estimator should keep an estimate book, and it is good practice to keep a separate book for each job, if it is of any size. Each item should be shortly but clearly specified. The estimated weight should be put against it, the cost of the raw material, the estimated time of workmanship and the rate of pay, and a column should be written up for the total cost, thus: Piece. Material. Price per Ton. Finished Weight. Bloom Weight. Material Price. Hours. Rate. Workmanship. Total. Bloom D rod steel, B.S.S. £ia i c. 2q. 21 Ib. 2C. i q. 7lb. £10 10 10 2S. 20$. £n 10 An extra cost would be added, because the total cost of machining is not merely the cost of the actual ingot plus the labour charge—there is an " over- head charge " to be added. Specialities of other Makers.—In the case of specialities, such as auxiliaries and furnaces, the prices of different makers would be put down, although only that of the successful tenderer would be carried forward to the finished column. This would enable the work to be referred back to expeditiously, in case of a change later on. The customer, for instance, might prefer to pay more to get some particular make of boiler feed-pump. Final Estimate Book.—From this book the finished estimate would be made up, and oncost charges and profit would be added. The finished book containing these two items is confidential, in many places the manager reserving the care of this book to himself. Should a contract be concluded on the basis of this estimate, the details as they are actually finished should be entered up in an abstract book, in which double columns should show the estimated weights, costs, &c., alongside the actual weights and costs. Only thus can the work of the estimating office be properly supervised and checked. Scales of Wages, Rates of Mechanical Operations, &c.—A scale of wages for different classes of work must be kept, also rates of speeds at which the work can be turned out; say, in machining, the table should give the surface which can be rough turned in a given time, also the rate for finish- ing cuts, &c., where this process obtains. In other classes of work a piece- work rate per 100 rivets may hold, or the rate may be so much per foot for smithwork on angle-iron, or, in the forge, a price per hundredweight for " light" and a price per hundredweight for " heavy " forgings. This all implies that the estimator shall make himself thoroughly familiar with his own shop practice. It may be necessary for him to get estimates from the foremen, or from rate-fixers, but so far as possible this information should be tabulated inside the estimating office, and as little reliance as possible should be placed on shop estimates, because shop conditions are peculiarly unfavourable to the accurate making of estimates.