By and by, Mr. Carl Hagenbeck, who had handled about forty polar bears to my one, wrote to us, offering a fine female polar as a mate to the survivor. She was conceded to be one-third smaller than the big male, but was fully adult. Without loss of time I answered, declining to make the purchase, on the ground that our male bear would kill the female. It was my belief that even if he did not at once deliberately murder her, he soon would wear her out by his rough play. Mr. Hagenbeck replied with the assurance that, in his opinion, all would be well; that, instead of a tragedy taking place, the male would be delighted with a female companion, and that the pair would breed. As convincing proof of the sincerity of his views, Mr. Hagenbeck offered to lose half the purchase price of the female bear in the event that my worst fears were realized. I asked the opinion of our head keeper of bears, and after due reflection he said: "Why, no; I don't believe he'd kill her. He's not a _bad_ bear at all. I think we could work it so that there would be no great trouble." Mr. Hagenbeck's son also felt sure there would be no tragedy. Quite against my own judgment of polar-bear character, but in deference to the expert opinion arrayed against mine, I finally yielded. The female bear was purchased, and on her arrival she was placed for three weeks in the large shifting-cage which connects with the eastern side of the great polar bears' den. The two animals seemed glad to see each other. At once they fraternized through the bars, licked each other's noses, and ate their meals side by side. At night the male always slept as near as possible to his new companion. There was not a sign of ill temper; but, for all that, my doubts were ever present. At last, after three full weeks of close acquaintance, it was agreed that there was nothing to be gained by longer delay in admitting the female to the large den. But we made preparations for trouble. The door of the sleeping-den was oiled and overhauled and put in thorough working order, so that if the female should dash into it for safety, a keeper could instantly slide the barrier and shut her in. We provided pike-poles, long iron bars, lariats, meat, and long planks a foot wide. Heartily wishing myself a hundred miles away, I summoned all my courage and gave the order: "Open her door, a foot only, and let her put her head out. Keep him away." The female bear had not the slightest fear or premonition of danger. Thrusting her head through the narrow opening, she looked upon the world and the open sky above, and found that it was good. She struggled to force the door open wider; and the male stood back, waiting. "Let her go!" Forcing the door back with her own eager strength, she fearlessly dropped the intervening eighteen inches to the floor of the den, and was free. The very _next second_ the male flung his great bulk upon her, and the tragedy was on.