448 THE POPULAR SCIENCE MONTHLY. 



But if it escapes the earth, and continue its course along its orbit, it 

 loses speed for the next sixteen years, until it passes the farthest part 

 of its orbit at its slowest pace, which is about a mile and a third per 

 second. In each revolution its velocity oscillates between these ex- 

 tremes. Its orbit is so vast that it takes thirty-three years and a quar- 

 ter to get round it. 



Such is a good picture of the course pursued by each member of 

 the great November swarm. There are countless myriads of meteors 

 in this mighty group, each one moving independently of the rest, each 

 one fulfilling its own destiny. Tbey form, together, an enormous 

 stream of meteors, the dense part of which appears to be about 100,000 

 miles in width, and of immense length. The orbit along which they 

 travel was represented on the diagram by an ellipse of 207 centimetres, 

 or close upon seven feet, long i. e., by an oval about as long and 

 broad as the hall-door of a house ; and the length, breadth, position, 

 and motion of the swarm in 1865, before it reached the earth, would 

 be represented on the same scale by a thread of the finest sewing-silk, 

 about a foot and a half or two feet long, creeping inward along the 

 orbit, the rear of the column having been between the orbits of Jupiter 

 and Saturn, and the front of it nearly as far in as the earth's orbit. 

 The actual train which is thus represented was so amazingly long that 

 even moving at the rate of twenty-seven miles a second, it took upward 

 of two years to pass the point where its path crosses the earth's orbit. 

 The earth passes this point on the morning of the 14th of November in 

 every year. The head of the dense part of the stream seems to have 

 reached the same point early in the year 1866. The earth was then in 

 a distant part of its orbit, but on the following 14th of November we 

 came round to the place where the great stream of meteors was pour- 

 ing across our path. The earth then passed through the swarm, just 

 as you might imagine a speck, too small to be seen by the eye, to be 

 carried on the point of a fine needle in a sloping direction through the 

 thread which represents the meteors. The earth took about five hours 

 to pass through the stream ; and it was Europe, Asia, and Africa, 

 which happened at the time to be moving forward. Accordingly, it 

 was upon this side of the earth, on that occasion, that the meteors 

 were poured, and they produced the gorgeous display in our atmos- 

 phere which many here must remember. In 1867, when we came 

 round again to the same place, the stream of meteors was still there, 

 America, this time, chanced to be the part of the globe which was 

 turned in the right position to receive the shower. In 1868 the mighty 

 swarm had not passed, and in subsequent years, when we came round 

 to the proper place, we still found ourselves among outlying stragglers 

 of the great procession. 



In 1799 Humboldt was traveling in South America, and on the 

 morning of the 12th of November in that year the November shower 

 was poured out over the New World. Humboldt's description of this 



