  The paper investigates the influences of the helicity on the gravitational
mass density, the field source, the charge continuity equation, and the mass
continuity equation etc in the electromagnetic field and gravitational field.
By means of the algebra of octonions, the magnetic helicity, the current
helicity, the cross helicity, the kinetic helicity, the field energy, the
enstrophy, and some new helicity terms can be derived from the octonion
definitions of the linear mentum and the force in some field descriptions with
different operators. The study claims that the gravitational mass density, the
field source, the charge continuity equation, and the mass continuity equation
will be impacted by the helicity, the field strength, and the vorticity of the
rotational objects and of the spinning charged objects in the gravitational
field and the electromagnetic field with their adjoint fields.
