The problem of the existence and analytical properties of asymptotic s
olutions of the equations of dynamics which approach a position of equ
ilibrium as t --> infinity is considered. This problem was solved by L
yapunov [1] in the case when the equilibrium is a non-degenerate criti
cal point of potential energy. In this paper we consider the situation
when the absence of a minimum of the potential energy cannot be deter
mined from the quadratic form of the expansion of the potential energy
in a Taylor series. It is shown that the asymptotic solutions can be
obtained in the form of a series in inverse powers of time, which cont
ains logarithms. If these series diverge, they are asymptotic expansio
ns for the solutions considered. The problem of the effect of gyroscop
ic forces on the existence of asymptotic motions in systems with a deg
enerate potential energy is considered. An analogue of Kelvin's theore
m is obtained on the impossibility of stabilizing the equilibrium by g
yroscopic and dissipative forces.