Page:Popular Science Monthly Volume 71.djvu/38
POPULAR SCIENCE MONTHLY
number have agreed that they are approximately correct. The oval area occupied by this volcanic bowl is thus over 100 square miles, an area half as large again as the District of Columbia.
The crater of Aso is both for size and structure unique among the craters of the world. The Hawaiian volcanoes, with which Aso shows the most resemblance, are of greater bulk, but their craters, which are usually spoken of as the largest in the world, can not compare in size with that of Aso. The crater of Haleakala, according to Dana, is 7½ by 2¼ miles in dimensions, and covers some 16 square miles. It has a greatest depth of 2,500 feet. The Kilauea crater, Dutton gives as 3½ miles long by 2½ miles wide and from 300 to 700 feet deep. The crater of Mauna Loa was measured by Alexander as 3½ by 1¾ miles in dimensions, with an area of 3½ square miles. The islands of Santorin south of Greece in the Mediterranean preserve the remains of a crater 18 miles in circumference, and Pantellaria, between Sicily and Africa, one with dimensions of 8 miles by 6. The two Italian crater lakes, Bolsena and Bracciano, are of great size; the one is oval with a long diameter of 9 and a short diameter of 7½ miles, and the other is a circle 6 miles wide. The crater of the volcano Palandokan in Armenia is said by Bonney to be 6 miles in width. Among the volcanoes of the Canary Islands, Scrope mentions the cirque of Teneriffe, which contains a pit 2,000 feet deep and a high peak within it, as being 8 miles long by 6 miles wide, and Bonney the crater on the island of Palma as 9 miles in diameter. A crater on Mauritius is said by Dana to have a longest diameter of 13 miles. Among the great volcanoes of Java, according to Scrope, Papandyang has a crater with measurements of 15 by 6 miles, and Bromo one with diameter of 4 or 5 miles. Crater Lake in Oregon, described by Diller, is one of the most perfect. This nearly round pit is 4 or 5 by 6 miles in dimensions and has a depth of 4,000 feet. But Aso surpasses them all, with a crater equaling 2 or 3 times the combined volumes of the three great Hawaiian craters mentioned.
The journey over the old floor in the midst of such novel surroundings is a unique and pleasing one, but the stupendousness of the scene comes over one more strongly when he looks down upon it later from above. Our little party chose the southern of the two forks and followed it up for mile after mile along its gentle upper course. The distances proved elusive. We looked across the plain to the wall on the other side and it was only a little way, but still as we went the goal seemed no nearer. The ascent from the point of outlet of the streams is at first rather steep. Within about a mile, however, the fork that we followed bursts off the level of the crater floor in a picturesque waterfall. It is called by the Japanese Aigaeri, or " trout-return," for beyond this the fish can ascend the stream no farther. The view upward to the moimtains surrounding the plain on all sides is mag-