u 



MOVEMENT 



time-curve of the distance traversed results from 

 the combination of these two movements. Figs. 31 

 and 32 show the details of the apparatus. A strip of 

 paper, the length of which is about one metre, passes 

 between cylindrical rollers which advance it a distance 

 proportional to the space traversed by the moving 



Kir.. 31. — Detaib of the odograph. The strip of paper, which has already received 

 a tracing of progression and re.-t, can be clearly ?een in position. One needle has 

 completed its journey, and a second, in iis turn, is just about to commence. 

 The needles, to the number of five, are arranged at a distance of six centimetres 

 from one another, along a steel band which passe* round the two rollers G by 

 mea> s of clockwork. At B can be seui the extremity of the shaft which imparts 

 the movement to the rollers. 



body. Each revolution of the wheel, representing a 

 distance of three metres, will advance the wheel of the 

 cylindrical rollers through a distance of one cog. This 

 is effected by means of a crank which runs along one 

 of the handles of the wheelbarrow. During this time 



