OF SUKVEYING INSTKUMENTS. 



73 



FIG. 538. 



538. Improved Spring Pocket Tape Measures, with linen or electrotyped steel tapes, 

 in brass, German silver, pearl or shell cases, with or without stops, 3 to 

 6 feet tapes ; brass, from Is. to 2s. 6d. each ; German silver (jig. 538) 



2s. 6d. to 5 



SCALES, SQUARES, RULES, ETC, 



539. Metford's Improved Set of four Pocket Scales, for architects and surveyors, 



in Eussia leather case, 2 16s., or two in separate case . 1 10 



Each scale is 6 inches in length, and a right-angled triangle in form ; two of them are 

 divided into decimals or tenths, and the other two into duodecimals or twelfths. Their contents 

 are marked on the ends of each. In the triangular form the divisions are placed on the edges, 

 the most useful scales on the acute angles, and a table of constants on the rectangles. The 

 scales thus obtained are 17 in number, fully divided, and reading off at the edges, viz., 

 1, 2, 3, 4, 6, 8, and 10 chains of 66 feet to the inch, and 6 inches to the mile j the mechanical 

 scales are -fa i TO 1 i i" and T inch > besides the French metre, the Rhineland foot = the 

 Prussian and Danish foot. The Spanish vara, Eussian vershokes, or any other foreign measure 

 may be substituted if preferred. 



Plotting Scales, ivory, divided on both edges, single or in* sets : 



540. 12 inch., 10 X 10, 20 X 20, to 50 X 50, 8s. Od. ; 6 inch, ditto . 050 



542. 12 inch. 60 to 70, 9s. Od. ; 6 inch. . . 060 



543. 12 inch. 80 to 100, 10s. 6d. ; 6 inch. . . 080 

 PLOTTING SCALES, boxwood, divided on both edges : 



544. 12 inch., 10 X 10, 20 X 20, to 50 X 50, 2s. 2d. ; 6 inch. . . 018 



545. 12 inch. 60 to 70, 2s. 4d. ; 6 inch. . . 019 



546. 12 inch. 80 to 100, 2s. 9d. ; 6 inch. . . 020 



