625 
metreton is introduced, the point A’, descends an amonnt A, Ax = 
u 
— t— , the point 2 an amount BB—= 2.2. 
L Q Le 
AA’ : 2 ; cine 
= 2 being constant, the series of points A'‚ and B are similar. 
BB x 
0x 
The lines (A', ) connecting their corresponding points, pass 
therefore through ane fixed point Bas Bs which divides the distance 
of the lines /4 and /g into parts whieh: are to each other as — 1: 2. 
The point B", which belongs to -the point B, lies at a distance 
x x 
«.B'B from this point, since the “force” falling along dj, hence 
1 1 
also the moment relative to B derived from this ‘‘force’’, increases 
linearly with the moment Mg. 
As B has descended over a distance «.BB relative to 5 the 
x (| al 
2 
point B” lies [BB ur above B. 
x ul 0 
! 1 
The ratio — — being constant, also the series of points A’, and 
BB, 
B" are similar, so that also the lines A’; B" pass through one point 
x x 
Pap", not indicated in the diagram. 
x 
The three angles of the variable triangle A’; Ill, B, (of which 
x 
‚III, B gives one position) move in three straight lines /4, lr and 
1 
lg passing through one point, while two sides rotate round fixed 
points. Hence also the third side must rotate round a fixed point 
lying on the line connecting the centres of rotation of the two other 
sides. 
If we further fix our attention on the variable triangle Ill, B",1V, 
x 
it appears that also the angles of this triangle move in three straight 
lines (lim, lg and liv) passing through one point, while two sides, 
viz. Ill, „IV and III, B, rotate round fixed points. 
The third side rotates therefore also round a fixed point P yy_y 
x x 
on A’,, B. 
0 
But then the side ,V ‚VI too has a fixed centre of rotation P'IV,V: 
For the sides ,IV,V and ,V,VI cut from the line /g, hence also 
from the vertical through P IV,V) a segment of constant length. As the 
