as and often better than they can in consciousness, when they largely rely upon an artificial time-computer. In doing this they may perform an intellectual process similar in all respects to the conscious act of calculating a distance between known points.
Third. This division covers a wide field of intellectual activity, and the inquiry is here directed to the result of systematically connected thought, omitting only original research which is considered later. Is there unconscious reasoning of a complex kind employed when old work begun in consciousness is carried on or brought to a logical conclusion unknown to the thinker, as in the cases of solving mathematical problems and the like? Let the facts speak for themselves:
1. Mr, T——, of Metuchen, New Jersey, writes: "I had earnestly been trying to make a trial-balance, and had at last left off working—the summary of the Dr. and Cr., sides of the account showing a difference of £2 10s. 0d., the Dr. side being so much smaller. The error I had not found on Saturday night when I left the counting-house. On this same Saturday night I retired, feeling nervous and angry with myself. Some time in the night I dreamed thus: I was seated at my desk in the counting-house and in a good light; everything was orderly and natural, the ledger lying open before me. I was looking over the balances of the accounts and comparing them with the sums in the trial balance-sheet. Soon I came to a small account having a debit balance of £2 10s. 0d. I looked at it, called myself sundry uncomplimentary names, spoke to myself in a deprecating manner of my own eyes, and at last put the £2 10s. 0d., to its proper side of the trial balance-sheet, shut up and went home. Here the dream abruptly ended. I arose at the usual Sunday time, dressed carefully, breakfasted, went to call upon some young lady friends, and to go to church, especially with one of them. Suddenly, the dream flashed on my memory. I went for the keys, opened the office, also the safe: got the ledger, turned to the folio my dream indicated. There was the account whose balance was the sum wanted, and which I had omitted to put in the balance-sheet where it was now put, and my year's posting proved correct."
2. Mrs. R——, of Wakefield, Rhode Island, writes: "When perplexed by work, often leave it and find the thing easy after a little while. Once, while working at a chess-puzzle for several evenings, I went to bed, fell asleep, and worked it correctly; sprang out of bed, found it correct, and wrote it down for fear of forgetting it; found it right in the morning, I had worked at the puzzle so long that it was perfectly familiar, and, before going to sleep, lay thinking of new moves; the right one was merely a continuation of my waking thoughts."
3. Mr. S——, of New York city, writes: "I remember but one instance, in which case, when about nineteen years of age, I correctly solved a mathematical problem, during a sound sleep, so far as I could judge, which had puzzled me before going to bed."