26 BENJ. PIKE'S, JR., DESCRIPTIVE CATALOGUE. 



The Universal Tube Compass, with points to turn. 

 (Fig. 29, page 29.) This instrument consists of two Ger- 

 man silver or brass tubes, connected by a joint as other 

 compasses, having other tubes sliding firmly and evenly 

 within them ; at the outer ends of the inner tubes are affixed 

 a joint and pieces, to which are attached the points, which 

 are fixed in pairs; the pencil point at one end, and a plain 

 point at the other, in one arrangement, and the ink point 

 and a plain point in the other arrangement ; each of which 

 is movable in a swivel, and can be turned round so as to 

 bring either point into use as may be required. When a 

 longer space is wanted than can be conveniently extended 

 in the ordinary state of the instrument, the movable tubes 

 can be drawn out, and thus a larger pair of compasses form- 

 ed. They also can be used as a beam compass within the 

 limits of the slides, having both the points turned parallel 

 to each other, and also perpendicular with the paper. 



Price, in German silver, $12.00. 



Beam Compasses (Figs. 30 and 31, page 27) are used 

 for describing large arches, and bisecting lines or arches. 

 These compasses consist of a long beam, made of brass or 

 wood, furnished with two brass boxes, the one fixed at 

 the end, the other sliding along the beam, to any part of 

 which it may be firmly fixed by a screw. An adjusting 

 screw is adapted to the box at the end of the beam ; by 

 this the point connected therewith may be moved with 

 extreme regularity and exactness. 



Price, $4.00 to 10.00. 



Drawing Pins (Fig. 32, page 29), are used for fastening 

 to the drawing board paper, for which purpose one is 

 pressed through each corner of the paper into the board, 

 firmly securing the paper thereby. 



Price, in brass, per dozen, 75cts. 



" in German silver, do. 88cts. 



Metal Centres, having two or more very delicate pins, to 

 fasten to the paper used in drawing, where the points of the 

 dividers are frequently to be placed on one centre, and 

 preventing the injury to the paper that would arise from 

 placin" 1 the points thereon many times. 



Price, 25 to 50cts. 



