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of lever (47) is taken away. This lever closes at *) the curcuit 
(H+ eee tee ee), Which affects magnet (MY!). | 
When weight (85) has fallen down. straight (in a metal tube (52) 
it presses down lever (48), that lifts by its shorter arm lever (47) 
and. opens the circuit of magnet (MY!). Instantaneously the device 
(37) is relaxed from magnet (MY!) by a spring (invisible on fig. 5) 
and the second-pendulum begins again to draw up the carriage. 
As the drum is a non-moving one, a second line would be drawn 
on the same spot as the first. Therefore the fallen weight closes a 
circuit at **) (etn), which affects magnet (MY). 
Armature (50) is attracted and a pawl with it. The pawl pulls on 
cogwheel (49) that is mounted on the axis of the drum (VIII). 
The latter is turned 1,5 m.M. The new line thus will be drawn 
1,5 m.M. from the preceeding one. As the dyum has a great inertia 
and the system was moved on some times more than agreed with 
one tooth of the cogwheel (49), the movement is moderated by an 
oil-pump (54), whereas a contra-pawl (51) prevents the turning back 
of the drum. When weight (85) rises again, the circuit is opened, 
as lever (48) is lifted by a weight on its shorter arm. 
In this way a registration has been obtained, at which the length 
of each line expresses in m.M. the time in seconds which the plant 
needs for an increase of 10 u. As the lines are drawn 1,5 m.M. 
apart, 15 c.M. of the paper corresponds to 1 m.M. growth (100 lines). 
Several precautions have been arranged to secure a safe record. 
In the first place, the record has to be stopped automatically, when 
the plant grows in a wrong way, i.e. when it ceases to make 
contact. In that case, the carriage (84) is drawn up entirely and 
pulls at the end on lever (55). The current, which affects magnet 
(MY), passes through this lever (omitted in fig. 4) and a small cup 
(56) with mercury. When the lever is lifted out of the mercury by 
the pressing carriage, the circuit is opened. 
To obtain a record over a long lapse of time, the use of several 
yards of paper is necessary. These have been rolled on a second 
drum and laid over a metal plate (57). So the pen has to write on 
the same level, while the drum (VIII) increases in bulk. — 
In order to get a straight abscissa the carriage has to stop always 
at the same starting-point. This is obtained by a metal block (45) 
and a small plate, connected with cylinder (83). The under-side of 
the table stops this plate, when the carriage reaches block (45). 
A second weight (58) has to pull the carriage, when the power of 
weight (85) is broken on lever (48). 
To prevent the tedious burning of the contacts on the switch 
