Through the resultant scarcity of labor, much land fell out of cultivation.
There is no difficulty in expressing the resultant by the method of symmetric functions.
The main branches of the resultant " tree " may be rendered as follows: [[Coraciomorphae Odontolcae..Colymbo-+Pelargoalectoromorphae..Ratitae Morphae Morphae ' 'Neornithes]] The Odontolcae seem to be an early specialized offshoot of the Colymbo-Pelargomorphous brigade, while the Ratitae represent a number of side branches of early Alectoromorphae.
It is also the custom to balance a proportion of the reciprocating masses by balance weights placed between the spokes of the wheels, and the actual balance weight seen in a driving-wheel is the resultant of the separate weights required for the balancing of the revolving parts and the reciprocating parts.
Another of Roberval's discoveries was a very general method of drawing tangents, by considering a curve as described by a moving point whose motion is the resultant of several simpler motions.