Call of nature

It appears from the evidence adduced that after the canvass had continued five or six consecutive hours, Mr. FORBES and Mr. DECKER, two inspectors went out (though not in company) as they say in "obedience to a call of nature," and were gone five or ten minutes, leaving the box containing the votes for member of Assembly sealed in the care of one inspector. . . .

I came here yesternight for a call of nature and to do what none can do for me[.]

. . . the little tree in the big forest of the huge national park behind which Mrs. Marie Dressor retreated from a roadside picnic with her husband and children, to heed a call of nature.

Cook's concentration may have been broken by a call of nature a few minutes earlier, when he held up play to visit the bathroom.