1796  (1911)  There is a fog like our Indian summer, with insufferable heat.
1830  . . . in November, and sometimes until the middle of December, the waning season, like the expiring efforts of a lamp, which now and then glimmers fitfully yet brilliantly in the socket, presents us with days to which there is no parallel in England. This sort of weather is called the Indian summer, and varies in duration, from a few unconnected days in some years, to as many weeks in others.
1965  A few had packsacks; some carried lunch pails with thermos bottles. A mercifully unseasonable Indian summer spared them all.