Climate and Time in Their Geological RelationsNote 146 — Chapter XVII · FORMER GLACIAL EPOCHS.—REASON OF THE IMPERFECTION OF GEOLOGICAL RECORDS IN REFERENCE TO THEM.Reading edition“Travels in North America,” vol. ii., p. 137.◇Copy noteReturn to CHAPTER XVII. FORMER GLACIAL EPOCHS.—REASON OF THE IMPERFECTION OF GEOLOGICAL RECORDS IN REFERENCE TO THEM.