No. 388.] MAINTENANCE OF THE EQUILIBRIUM. 315 
There is needed for this a very finely calculated and graduated 
intensity of action by each of the components of motion, a 
process which is designated as coérdination of the muscles, in 
this case as static codrdination. 
Let us again take the stick of wood, which would not remain 
standing before, and fasten a number of strings to its upper 
end. Now let us set it up again and pull slightly in different 
directions, laterally, and a little downwards. Probably it will 
at first fall over to one side toward the strongest pull, but if we 
modify the strength with which it is drawn in the different 
directions, we shall finally cause it to remain quietly standing 
in a vertical position. A condition of equilibrium has been 
reached by the proper co6drdination of the forces acting, the 
same as occurs with a standing man through the coérdination 
of muscles. 
Intentionally I lay- special stress upon this unusually impor- 
tant factor of codrdination of the muscles, which takes a signi- 
ficant part in each muscular act, even though the result be 
unsuitable to the purpose which prompts it. Indeed, we may 
go still farther and say that wherever several factors cooperate 
for the attainment of a uniform: result, a proper determination 
of the intensity with which each shall act is absolutely necessary. 
Without going into complex social conditions I may give an 
illustration from art. 
If, in the well-known Seventh Symphony of Beethoven, the 
bassoonists conceive a desire to play fortissimo in the wrong 
place, the effect will be destroyed as much as if the contrabass 
were to play a very light piano in a place written forte. Each 
player finds certain signs with his notes, the dynamic signs of 
expression, which show him not what, but how, he ought to 
play. 
The corresponding signs which make known to our brain 
how each muscle must act for the attainment of static coördi- 
nation are imparted to it by different sense organs. As the 
first, though not the most important of these, I mention the 
touch sensations of the sole of the foot. If we stand, and still 
more if we walk, we feel the ground beneath our feet. It needs 
no long reflection to perceive how difficult simply standing 
