Most architects stipulate in the specification that on the completion of the work all drawings are to be returned by the builder. Whether this be done or not, all drawings referring to the completed building should be collected together and done up into a huge roll, docketed and put away among the records of the office.

Inks and instruments have been largely dealt with in the previous chapter, but before discussing brushes and colours it may not be out of place to say a word about the many architects' and engineers' coloured inks which are advertised as being waterproof. Probably more drawings have been ruined by falling into this snare than from any other cause. The majority of the Indian and Chinese inks are undoubtedly waterproof, but there is scarcely a coloured ink which will bear colouring over without "running." Drawings are often finished up in ink with the sections, dimensions, drains, and what not drawn on in red, blue, and green, relying on the waterproof qualities of the inks, and then, when the colour washes are laid on the inks run in such a terrifying manner as to qualify the drawing to compete with a rainbow. It is better not to use these "indelible" (?) inks until all the colouring has been done, and then, as there is no risk of "running," the ordinary colours in the colour box may be used instead. Coloured inks are in no way necessary to an architect.

The most convenient form in which to buy colours is undoubtedly that lately introduced by Windsor & Newton. These colours, which include Venetian Red, Yellow Ochre, Sepia, Lamp Black, Prussian Blue, and all the ordinary colours used by architects, are made up in hexagonal cakes about 2 inches long, and contain approximately as much colour as two and a half of the ordinary cakes. As they only cost as much as a cake and a half of the ordinary size, the saving is obvious.

The conventional colours used for 1/8 scale drawings differ in some respects from those employed for details, and there is also a general difference between the practice in London and in the Provinces.

According to the London practice, on 1/8 scale drawings brickwork in elevation is coloured very lightly with a tint of Light Red or Venetian Red, and brickwork in section by the same colours laid on more thickly. In the Provinces crimson lake is often substituted for the other reds, and this colour is also used by engineers and surveyors not only for walls, but also for plans of estates, etc. Stone is fairly universally indicated in elevation by a very pale tint of yellow ochre (or else it is left white with the courses shown by the inking in). In section it is indicated by a bold tint of indigo. On 1/8 scale drawings in London, woodwork is represented in section and elevation by sepia, a darker tint being employed for sectional parts. On detail drawings sepia is used for wrought wood in section, and burnt sienna for unwrought wood. As has been stated earlier in this chapter, elevational parts need not always be coloured on detail drawings. In the Provinces yellow ochre is used for woodwork in elevation, and burnt sienna for sectional parts, whether wrought or unwrought. Internal or external plasterwork is indicated by a tint of yellow ochre on all drawings, but where required for details, as in mouldings and sections, purple is generally employed. This tint is best made by mixing crimson lake and Prussian blue. Ironwork in section and elevation is universally represented by prussian blue, with a darker tint for the sections. It may be remarked here that all sectional parts are coloured more darkly than the same material in plan or elevation. Concrete is indicated by Payne's grey. Leadwork, the little that appears on elevations, is coloured by any blue which does not cause confusion with the other blues which may be employed in the same drawing. In leadwork details a bluish green tint should be used. Floor tiles and mosaic are coloured with a tint of crimson lake and light red mixed, while for roof tiles the same colours are employed, but often with sepia or burnt sienna added so as to more closely approximate to the actual colour of a tile. Slates are indicated by a greenish grey, which may be obtained by mixing Payne's grey and burnt sienna or indigo and burnt sienna. For windows in elevation the glass can be coloured with a light tint of either of the latter, or, better still, with a mixture of prussian blue and sepia, or prussian blue and burnt sienna. Some architects prefer to use a light wash of lamp black for this purpose. Green is hardly ever used alone, except perhaps for glass in section, and this occurs rarely. Lamp black is the best black to be obtained when walls or sections have to be blacked in instead of coloured. It is a dull dead black which can be laid on perfectly evenly, and has not the bronze-like sheen which is the drawback to the use of Indian ink for this purpose.

The colours, to recapitulate, which are required in an office for working drawings are: - light red (or Venetian red), crimson lake, yellow ochre, indigo, sepia, burnt sienna, prussian blue, Payne's grey, and lamp black.

Brushes can be obtained in great variety, but the architect requires but few for office work. The most satisfactory will be found to be the sable-hair brushes in metal ferrules or tubes; and although these can be obtained in sizes from 1 to 12, the draughtsman will only need to supply himself with, say, No. 4 for filling in walls and small pieces, No. 7 or 8 for small washes, and No. 11 or 12 for large washes. Camel-hair brushes are cheaper, but the hairs lack the suppleness of sable, and do not spring or respond under the touch. Those who are used to working with sable will find it very difficult to change to camel-hair brushes, and it is a matter of universal experience that the sable brushes are the cheapest in the long run. Brushes ought to be washed out in clean water after use, the surplus water being "thrown" from the brush, and the bristles lightly brushed over the palm of the hand to bring them to a point before they are put away to dry.