This section is from the book "Elements Of Construction", by Charles A. King. Also available from Amazon: Elements of construction.
Brushes. For stain and filling, a cheap brush of any suitable size will do, a flat brush generally being used upon ordinary work. For shellac and varnish, a fine brush will give better results than a coarse one; usually, however, it is the best practice to use as large a brush as the nature of the work will permit, as it will hold more and therefore cover more surface and show fewer laps. Brushes from 1 1/2" to 2" in width will be found satisfactory for the work of pupils and amateurs.
The care of brushes is an important part of the work of those who use them, as neglect or carelessness may destroy a valuable brush overnight. Unless a brush is to be used again soon, it should be thoroughly cleaned. In cleaning a stain, filling, paint, or varnish brush, use benzine or turpentine; but for a shellac brush, use wood alcohol, cleaning all the small particles off. To obtain the best results, all brushes should be washed in hot, soapy water, and thoroughly rinsed in clean water. Shellac and varnish brushes should not be changed from one to the other unless thoroughly cleaned. Never allow a brush to stand upon its side for more than a few minutes at a time, as a wrong direction is easily given the bristles, and a valuable brush may be quickly destroyed by a little carelessness or negligence.
Old brushes, well broken in and cared for, will give better results than new brushes; therefore they should be treated with every possible consideration.
 
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