Sentence:  Whether,nb..., the construction of additional roads...would present a case in which the exaction of prohibitory or otherwise onerous rates may be prevented, though it result in an impossibility for some or all of the roads to <WSD>make</WSD> expenses, we need not say; no such case is before us. 
Meaning of the word marked with <WSD> tags:  To pay, to cover (an expense); (chiefly used after expressions of inability.)