The Psychology of Speculation by Henry Howard Harper

There are but few things more unbalancing to the mind than the act / of suddenly winning or losing large sums of money. A few years ago / at Monte Carlo I was in company with a friend, a well known man of / affairs who while there played at roulette nearly every day, merely as / a pastime. He was of mature age, naturally methodical, conservative, / temperate and cool-headed. He made it an unalterable rule to limit / his losses to $200 at any one sitting, and on losing this amount he / always stopped playing. His bets were usually limited to two dollars / on the numbers, and never doubled except for one turn of the wheel / when his number won. He generally played three numbers at a time; never / more than four. For ten consecutive sittings luck was against him and / each time he had lost his stake of $200. I saw him get up and leave / the room, apparently in a state of disgust. An hour or so later I / discovered him at a roulette table in another room stacking his chips / in piles on a dozen or more numbers. Now and again when he exceeded the / limit the watchful croupier reduced his bets and pushed a few disks / back to him. In addition to betting on the numbers he was staking a / thousand franc note on one of the three columns, another thousand on / the colors, and a like amount on the center dozen. In one run he lost / seventeen consecutive bets on red, of a thousand francs each. His eyes / were bloodshot, his fingers twitched, and plainly he was under the / strain of great agitation. He continued to play for three hours or so, / when all of a sudden he got up, stood for a moment looking dazedly / about, then left the table. He afterwards told me that he lost twenty / thousand dollars; and that he hadn't the slightest recollection of / anything that happened during the play, nor did he realize the amount / he was betting.

In this connection, it is a fact not generally known, / that many rich men sign printed cards of instructions to the proprietor / of a certain well known gambling club in the South, directing him / to stop their play and refuse them further credit beyond a certain / specified sum on any one day or evening of play, and refusing to become / responsible beyond that amount. If men who trade in the stock market / were to impose like restrictions upon their transactions the losses / would in many cases be greatly minimized.