This section is from the book "Shop Projects Based On Community Problems", by Myron G. Burton. Also available from Amazon: Shop Projects Based on Community Problems.

Yellow Pine (Chap. III.,
Par. 48) or any soft wood.
1 pc. 7/8"x6 1/4"x21 1/2" S 2 S
Top. 1 pc. 7/8"x7 1/4"xl9 1/2" S 2 S
Back. 1 pc. 7/8"x5"xl0" S 2 S
Brackets. 12-6d finishing nails.
The bracket shelf is one of the best-known and oldest forms of equipment found in the home. This article of furniture admits of more variations in size, function and style than possibly any article found in house equipment. The old-fashioned long mantle above the fireplace was one form of bracket shelf. Other numerous forms serve various purposes, such as a place for the family clock, or in some instances a sort of "catch-all" for things which have no better place.
In designing a bracket shelf you should consider very carefully for what purpose it is to be used, and first of all make it sufficiently substantial to serve its purpose properly, then consider the point of making it attractive in appearance.
References:
Woodworking for Beginners, Wheeler. G. P. Putnam's Sons, New York. Elementary Woodwork, F. H. Selden. Rand-McNally Co., Chicago. Beginning Woodwork at Home and in School, Van Duesen. Manual Arts
Press, Peoria, Ill. Woodworking for Amateur Craftsmen, Griffith. Popular Mechanics Co.,
Chicago. Our Trees, How to Know Them, Emerson & Weed. Lippincott Co.,
Philadelphia.
Bracket Shelf

Suggestions For Original Design

No. 1

No.2

No. 3

No. 4

No.5

No.6

No.7

No.8
Select one surface for a working face (Chapter II., Paragraph 2). Plane one edge perfectly straight and square with the working face. Mark this the working edge (Chapter II., Paragraph 4). Plane one end exactly square with the working face and the working edge. Mark this the working end (Chapter II., Paragraph 5). Gauge the width (Chapter II., Paragraph 6) on both surfaces; plane to the gauge line. Measure and cut the length.
 
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