The present tendency therefore is to throw more responsibility than of old on the drawing-office staff, in harmony with the tendency towards greater centralization of authority. Much of detail that was formerly left to the decision of foremen and skilled hands is now determined by the drawing-office staff. Heterogeneity in details is thus avoided, and the drawings reflect accurately and fully the past as well as the present practice of the firm. To so great an extent is this the case that the preparation of the tools, appliances, templets, jigs and fixtures used in the shops is often now not permitted to be undertaken until proper drawings have been prepared for them, though formerly the foreman's own hand sketches generally sufficed. The practice of turret work has been contributory to this result. In many establishments now the designing of shop tools and fixtures is done in a department of the office specially set apart for that kind of work. The growing specialization of the engineer's work is reflected in the drawing office. Specialists are sought after, and receive the highest rates of pay. A man is required to be an expert in some one branch, as electric cranes or hydraulic machines, steel works plant, lathes, or heavy or light machine tools. The days are past in which all-round men were in request. In those firms which manufacture a large range of machinery, the drawing-office staff is separated into departments, each under its own chief, and there is seldom any transference of men from one to another. Although in the majority of instances designs and drawings are completed before the manufacture is undertaken, exceptions to this rule occur in connexion with the work of standardizing machines and motors, for repetitive and interchangeable manufacture on a large scale. Here it is so essential to secure the most minute economies in manufacture that the first articles made are of a more or less experimental character. Only after no further improvement seems for the time being possible are the drawings made or completed for standard use and reference. In some modern shops even standardized drawings are scarcely used, but their place is taken by the templets, jigs and fixtures which are employed by the workmen as their sole guides in machining and assembling parts. By the employment of these aids locations and dimensions are embodied and fixed absolutely for any number of similar parts; reference to drawings thus becomes unnecessary, and they therefore fall into disuse. The mechanical work of the drawing office is confined strictly to orthographic projections and sections of objects. Perspective views are of no value, though occasionally an object is sketched roughly in perspective as an aid to the rapid grasp of an idea. Drawings involve plans, elevations, and sectional views, in vertical and angular relations.