  The bulk properties of nodal line materials have been an important research
topic in recent years. In this paper, we study the orbital magnetic
susceptibility and the Hall conductivity of nodal line materials using the
formalism with thermal Green's functions and find characteristic singular
behaviors of them. It is shown that, in the vicinity of the gapless nodal line,
the orbital magnetic susceptibility shows a $\delta$-function singularity and
the Hall conductivity shows a step function behavior in their chemical
potential dependences. Furthermore, these singular behaviors are found to show
strong field angle dependences corresponding to the orientation of the nodal
line in the momentum space. These singular behaviors and strong angle
dependences will give clear evidence for the presence of the nodal line and its
orientation and can be used to experimentally detect nodal line materials.
