METEORITES OF NORTH AMERICA. 383 



The observations at Bloomington, Indiana, and Wooster, Ohio, indicate that in a flight of 200 miles eastward from 

 Rochester the altitude diminished from 38 to 29 miles. The elevation when over Erie County, Pennsylvania, was 

 almost certainly less than 30 miles, probably not more than 25. After the explosion, near the southwestern border of 

 New York, the meteor became almost immediately extinct. In view of these facts it seems extremely improbably that 

 any part of the mass could have escaped out of the atmosphere. What became of the dissevered fragments, or why 

 none have been hitherto found near the terminus of the track, may be difficult of explanation. 



I have not learned that the time of the meteor's visibility was by anyone accurately measured. The slowness of 

 the apparent motion was, however, very remarkable, being compared by many to that of a flock of wild geese. Several 

 observers estimated the duration of flight at nearly two minutes. The velocity with reference to the earth's surface 

 was probably between 8 and 12 miles per second, and with reference to the sun, between 25 and 30. 



Smith 5 described the meteorite as follows : 



The passage of this meteorite through the earth's atmosphere has left but a small souvenir of its visit. It was well 

 observed at Bloomington, Indiana, latitude 39° 12' N., longitude 36° 32' W., by the distinguished astronomer Pro- 

 fessor Kirkwood, who communicated to me at the time his observations; and he has subsequently given them more 

 in detail to the American Philosophical Society, with the observations he had collected from others. I will therefore 

 simply give a summary of the phenomena attending upon its flight before describing the chemical and mineralogical 

 characteristics of the stone which fell. 



The bolide made its appearance about 9 o'clock p. m., December 21, 1876, and was of extraordinary magnificence. 

 It passed eastward over the States of Kansas, Missouri, Illinois, Indiana, Ohio, and parts of Pennsylvania and New 

 York. Although no observations were made in the two last-mentioned States, still Professor Kirkwood is doubtless 

 correct in defining this as its course. At Bloomington its elevation was 15 degrees. According to the calculation, 

 the length of its observed track was from 1,000 to 1,100 miles, one of the longest on record. Its height is supposed to 

 have been 38 miles above the place where the small fragment fell from it. 



In various parts of its track it threw off fragments, accompanied with the usual rumbling noise and commotion 

 in the atmosphere common to the flight of these bodies. When crossing Indiana, the main body was followed by a 

 train of smaller bolides, many of them of the apparent size of Venus or Jupiter. Its velocity in reference to the earth's 

 surface appeared to be from 8 to 12 miles per second. The pyrotechnic display is said to have been transcendently 

 beautiful, hardly equalled or surpassed by any previous occurrence of the kind. The cause of this brilliancy lay in 

 the physical structure of the body, which will be detailed farther on. 



The fragment which fell. — The only fragment of this bolide known to have fallen was one found on the farm of Mr. 

 Morris, 3 miles northwest of Rochester, Indiana, latitude 41° N., longitude 86° W. This farmer heard the explosion, 

 and shortly afterwards noticed a body strike the ground not far from him. There were 6 inches of snow upon the 

 ground, and on the following morning he found the stone, which had rebounded to a short distance from the place 

 where it first fell, it not having penetrated the ground. The entire stone did not weigh 400 grams; and, as we have 

 not heard of the fall of any other mass, it is reasonable to suppose that it was dissipated into very minute fragments 

 and dust, as in the case of the Hessle stones and other similar falls. 



The manner in which the molten matter of the exterior of many of these meteorites is swept over their surfaces, 

 in shining streaks, covering freshly broken surfaces, shows clearly that this disintegration is constantly and rapidly 

 going on in these bodies during their passage through the air. I have in my collection many fine examples illustrating 



this fact. 



Professor Kirkwood is of the opinion that this bolide never passed out of our atmosphere, which is in accord with 

 my general view on this subject, viz, that a bolide rarely, if ever, gets entangled in our atmosphere without being 

 entirely reduced to fragments or powder. 



The stone has been broken up into many small fragments, of which I have fortunately secured a good portion. 

 Others have been lost and a few have found their way into collections. With the exception of the largest specimen 

 in my collection, weighing 95 grams, hardly any other fragment weighs over 30 grams. It is important to treasure 

 these specimens, small as they are, for it is a remarkable stone of its type. It is of the pisolitic variety, very friable, 

 of a gray color, easily crushed under the fingers into light powder (some of it to fine dust), and to small globules, some 

 of them perfectly spherical, of which I have specimens 2 mm. in diameter. It resembles more closely the Aussun 

 stone than any other I know of, although much more friable. This peculiar structure, so often seen in many parts 

 of meteoric stones, has recently attracted much attention, Professor Tschermak, of Vienna, having recently published 

 an interesting paper on the subject. 



The specific gravity of the stone, taken with several average specimens, is 3.55. There is nothing peculiar about 

 the coating on the specimens I have examined; it is of a dull black and quite rough. 



Chemical examination— The stony part of the meteorite, separated almost perfectly from the metallic part, still 

 contained a notable portion of troilite that could not be separated mechanically. The amount of sulphur found in 

 that part of the meteorite indicated the amount of troilite present, viz, 3.31. 



