克莱因瓶是一个不可定向的二维紧流形，而球面或轮胎面是可 克莱因瓶 克莱因瓶 定向的二维紧流形。如果观察克莱因瓶，有一点似乎令人困惑－－ “67P/楚留莫夫-格拉希门克”彗星 [67] 在太 CHAPTER X. TOBACCO OFFERINGS. 1808. It was a beautiful moonlight evening in August. A shadowy haze lingered over the river, which glistened and sparkled in the moonlight. The Chief and several members of his family were seated on the beach in front of the Wigwam listening to the Honorable Joseph Papineau, who, with his son, Louis Joseph, had come up in a canoe to see the falls. The former had recently purchased from Bishop Laval the unsettled seigniory of Petit Nation, and had erected an unpretentious cottage, which he occupied during the summer months. HON. LOUIS JOSEPH PAPINEAU AND MADAME PAPINEAU. From Morgan\\'s "Types of Canadian Women" (copyright, 1903), by permission. HON. LOUIS JOSEPH PAPINEAU AND MADAME PAPINEAU. From Morgan\\'s "Types of Canadian Women" (copyright, 1903), by permission. "It was a lovely vision," said Mr. Papineau, who had just performed the feat of canoeing to the foot of the Chaudiere Falls for the first time. "On our return we climbed the rugged cliff on the south side, and never shall I forget the panorama that spread out before us. The sun, sinking slowly behind the Laurentian hills, had clothed himself with a robe of splendor. The long reflections lay soft on the waters of the river below. The clouds of ascending mist from the Chaudiere took a thousand shades of color as the western sky faded slowly from crimson into gold and from gold to green and gray, and finally displayed dark shapes, out of which imagination might well have formed a thousand monsters.* * Louis Joseph, afterwards known as the Demosthenes of Canada, and who almost succeeded in making Canada a Republic, with himself as President, was evidently much impressed with the scene, which he described as follows: "Le soleil etait pret decendre sous l\\'horison, la mureille tout limpide etait d\\'une transparence vivre, tout penetree de lumiere vaguement prismatiseé." "As we watched the gathering shadows my thoughts went back two hundred years, to the time when Champlain went on his first trip up the \\'Riviere des Algoumequins,\\' as he called it. About two years before he took the trip he sent Nicholas de Vignan, a young Frenchman, up the river with some friendly Indians, and Nicholas had returned with the marvellous story that he had reached the North Sea. He said that the journey could be made in a few days. He also gave an account of having seen the wreck of an English ship. "Champlain was completely taken in, and lost no time in starting off to verify the discovery for which the world had been looking for some time. His fleet consisted of two canoes with two Indians and three Frenchmen, one of whom was De Vignan. It was in May, when the river was at its height. When they reached the Gatineau the Indians told him that their tribe were often compelled to conceal themselves amid the hills of the Upper Gatineau from their dreaded enemies, the Iroquois. When Champlain beheld the twin curtain falls yonder, \\'like a slow dropping veil of the thinnest lawn,\\' he exclaimed, \\'Le Rideau! Le Rideau!\\' The Indians told him that the waters formed an arcade under which they delighted to walk, and where they were only wet by the spray. As they rounded the lofty headland opposite he saw the cloud of mist rising from the falls, which the Indians called the \\'Asticou,\\' which means \\'Chaudiere\\' in French, or \\'kettle\\' in English, for the water has worn out a deep basin into which it rushes with a whirling motion which boils up in the midst like a kettle. "You have probably been close enough to have seen it, Madame?" he said, addressing Mrs. Wright. "No," she replied, "I have always been too timid to venture so near to it in a canoe." "Champlain said," continued Mr. Papineau, "that he paddled as near as possible to the falls, when the Indians took the canoes and the Frenchmen and himself carried their arms and provisions. He described with great feeling the sharp and rugged rocks of the portages to pass the falls and rapids until at last, in the afternoon, they embarked upon the peaceful waters of a lake where, he said, there were very beautiful islands filled with vines and with walnut and other agreeable trees." "There are no walnuts on the islands of Lake Chaudiere," interrupted Bearie, "I am quite sure." "He probably saw a butternut tree," said young Louis Joseph, "and thought it produced walnuts." "Champlain\\'s journey came to an abrupt close a few days afterwards," said Mr. Papineau, "when he reached Allumette Island, about seventy miles farther up the river. There was a large settlement of friendly Algonquins, called \\'Les Sauvages de l\\'Isle,\\' and Champlain tried to obtain several canoes and guides to proceed farther. They, however, had their own commercial reasons for keeping the French from the upper country, and they warned him of the danger of meeting the terrible tribe of the Sorcerers. Champlain said that De Vignan had passed through all these dangers. The head Chief then said to the impostor: "\\'Is it true that you have said that you have been among the Sorcerers?\\' "After a long pause he said: \\'Yes, I\\'ve been there.\\' "The Indians at once threw themselves upon him with fierce cries as if they would have torn him to pieces, and the Chief said: "\\'You are a bold liar. You know that every night you slept by my side with my children. How have you the impudence to tell your chief such lies?\\' "The upshot was that Champlain returned down the Ottawa, followed by an escort of fifty canoes. "When the party reached the Chaudiere the savages, he said, performed their mystic rites. After having carried their canoes to the foot of the Falls, they gathered in a certain spot where one of them, provided with a wooden dish, passed it round, and each one placed in the dish a piece of tobacco. "The collection finished, the dish was placed in the midst of the band and all danced around it, chanting after their fashion. Then one of the chiefs delivered a harangue, explaining that from olden times they had always made such an offering, and that by this means they are protected from their enemies and saved from misfortune, for so the devil persuades them. Then the same chief took the dish and proceeded to throw the tobacco into the Chaudiere, amid the loud shoutings of the band. \\'They are so superstitious,\\' said Champlain, \\'that they do not believe that they can make a safe journey if they have not performed this ceremony in this particular place.\\' "The Chief proceeded to throw the tobacco into the Chaudiere." "The Chief proceeded to throw the tobacco into the Chaudiere." "Ah, Monsieur," Mr. Papineau continued, "it stirred my soul as I stood on that rocky cliff and thought of how many canoes of heroic missionaries, Indian braves and cheery voyageurs have paddled these waters and torn their feet on the rocky shores, going, some of them to death and some to tortures worse than death. As we drifted down with the current in the moonlight the gentle breeze in the pines along the shore seemed to be whispering sad tales of other days." Mr. Papineau, who had spoken with such animation and fluency, relapsed into silence for several minutes, then, rousing himself, said, with even greater enthusiasm and vigor: "Providence has crowned our lives with great blessing since the heroic Daulac struck the death-blow to the power of the Iroquois in this country, and since the English undertook the responsibility of its government. Though I am proud of the fact that every bone and muscle, nerve and sinew within me is French, though I dearly love my Mother Country and my fellow countrymen, I have no hesitation in making the solemn assertion that our country has enjoyed a greater degree of prosperity under the new regime than it ever did under the old. But it must ever be remembered that much of the foundation of that prosperity was laid in the blood of the early French martyrs and in the heroic achievements of the early French settlers." It seemed incredible to the visitors that in a settlement of so recent date their host should have been able to show them a grist-mill, a saw-mill, a vegetable alkali factory, a tannery, a small foundry, a tailor shop, a bakery, a general store, and a hemp-mill, giving employment to over one hundred men. Fortunately for the pioneers of the Ottawa, they were not dependent upon the small revenue derived from the cultivation of the land, but had other resources which afforded them much greater remuneration. The British Navy, which hitherto had been dependent upon Russia for its cordage and lumber, had to look elsewhere for its supply of hemp and timber, owing to the ports of the Baltic having been closed to British ships. The price of hemp having risen from ￡25 to ￡118 per ton, they undertook the cultivation of it, and raised over three-fourths of the amount raised in Lower Canada at that time. The exportation of lumber and vegetable alkali, or potash, were also great sources of revenue. In the new clearances were tons of wood ashes from which the lye was extracted and boiled till it looked like molten iron, a barrel of which sold at that time for thirty dollars. Prosperity and success crowned every commercial enterprise upon which they ventured until fire swept every mill, factory and dwelling in the thriving little village out of existence, including thousands of dollars in cash in a small safe in the office, quantities of wheat, hemp, sawn lumber, laths and general merchandise. As there was no compensation in the way of insurance, the loss was much felt. Philemon Wright was not the man to be deterred from climbing the ladder of success, even though he had to mount it by the rungs of adverse circumstances. Though the loss sustained was great, almost overwhelming, he rose above it with a courage which yielded not to disappointment or failure. The cause of the fire long remained a mystery. That it was the work of an incendiary was beyond question. Various theories were advocated by the settlers, but suspicion rested upon Machecawa, who, it was alleged, had been seen by the bookkeeper at a late hour lingering about the mills, a suspicion which gained no credence with the Chief and his family.阳系的周围还包裹着一个庞大的“奥尔特云”。星云内分布着不计其数的冰块、雪团和碎石。其中的某些会受太阳引力影响飞入内太阳系，这就是彗 [76]  在超新星爆发的过程中所释放的能量，需要我们的太阳燃烧900亿年才能与之相当。[77]  超新星研究有着关乎人类自身命运的深层意义。如果一颗超新星爆发的位置非常接近地球，目前国际天文学界普遍认为此距离在100光年以内，它就能够对地球的生物圈产生明显的影响，这样的超新星被称为近地超新星。有研究认为，在地球历史上的奥陶纪大灭绝，就是一颗近地超新星引起的，这次灭绝导致当时地球近60%的海洋生物消失。[78]

克莱因瓶是一个