200 



NEGRETTI AND ZAMBRA, HOLBOEN VIADUCT, B.C., 



DIRECTIONS FOK USING THE INDICATOR. 



588 Before working, a sheet of metallic paper is placed around the drum, and fastened to it 

 by means of the two clips, The cord is then attached to the most convenient part of the 

 piston rod or other part of the engine working in unison with it. The Indicator is 

 fastened to the cylinder of the engine by means of the cock and coupling. The small 

 leading wheels may be turned in any direction required. To change the spring, unscrew the 

 nut at top, through which the piston rod (of Indicator) works, and by lifting the arm which 

 supports the parallel motion, the piston rod will come out. The pencil can be removed from 

 or pressed against the paper by lifting or pressing the stud connected to the slotted bar 

 which the pencil works. 



It will be necessary, in sending orders, to specify particularly the number of springs 

 required and the pressure they will have to indicate. 



All the springs will fit every instrument, and they can be readily changed by any one. 



The springs are made to ten scales, as follows : 

 No. 



each 



s. 

 7 10 

 70 

 10 

 01 

 10 

 04 

 09 

 08 



d. 

 

 

 

 6 

 

 

 

 



PRICES. 



Indicator with one spring, &c., in box, fig. 587 



Ditto ditto, Smaller size . . 



Extra Springs (with scales) . . 



Paper Cylinder Spring ...... 



Arrangement for Oscillating Engines . . . 



Metallic Paper ..... per packet 



Treatise on Indicator . . . New Edition 



Extra Stop Cock ...... . 



Three-way Cocks for taking diagrams from top and 

 bottom of Cylinder without shifting the Indicator 



Elbow, for attaching the Indicator to horizontal 

 Engines ........ 



Connecting Pipes made to order. 



Spring No 1 has been specially adapted to indicate the vacuum on a large scale in 

 engines or pumps which work at high pressures. The springs showing pressures 

 above 80-lbs. will be made to indicate the vacuum also when so ordered, and springs 

 will be made also to any other scale desired. 



COUNTING, TALLYING, MEASURING, AND REGISTERING 



MACHINES, OR ENGINE COUNTERS. 

 589 Improved Engine Counter, for counting Oscillating motion, Reciprocating 



200 



066 



Strokes, or Revolutions in machines. 



4 figures, counts up to 10,000 



5 100,000 



6 1,000,000 



7 10,000,000 



s. 



2 16 

 33 



3 10 



4 10 



590 Harding's Patent Speed Indicator. This instrument has been designed for 

 showing without counting or the use of a watch, by the position of an index on a dial, 

 the actual rate of speed at which any Machine or Engine is at any moment revolving. 

 The Speed Indicator enables the Engineer to see at a glance the variation in 

 the rate of speed at which his machinery is running and detect causes of irregularity 

 and run his engine at normal speed, Price, 5 10 



