198 MEMOIRS NATIONAL ACADEMY OF SCIENCES, VOL. XIII. 



In its passage the meteor was seen throughout all Iowa, and observers report it from Kansas, Dakota, and 

 Minnesota. 



However exaggerated the press reports may have been in certain instances, the fact of its splendor stands never- 

 theless; so, too, the fact of the terror which the sudden light, the hissing passage, and terrific explosion inspired in the 

 people of northern Iowa, especially Winnebago County and immediate vicinity. Reports from all the towns and cities 

 for many miles around Winnebago County liken the noise of the explosion to heavy cannonading, accompanied by 

 a "rushing sound " or unearthly hissing and a noticeable tremor which caused the citizens to fly from their houses to 

 inquire into the cause. This vivid display occurred in the face of a bright spring sun, and an almost cloudless sky. 

 The dazzling head, likened to the moon in size, "sputtering" and throwing off a long train of sparks; the heavy line 

 of black smoke left in its wake to mark its course for a full 10 or 15 minutes; all were seen and marvelled at by the 

 people of several States. 



Its course to the eye was from southwest to northeast, and its inclination to the earth most commonly judged to be 

 about 55. One well-authenticated but surprising report comes from Tabor, in the extreme southwestern corner of 

 the State, to the effect that the "noise there was like thunder, and was compared by some to an earthquake shock, 

 the jarring of the ground being so evident; and that four distinct explosions were observed by one." This is a point 

 of considerable interest, for at Grinnell but faint noise, if any at all, accompanied the transit. Although the clamor 

 over a hotly contested game of ball on the athletic field of the campus hindered the students and faculty, who saw it, 

 from making careful observations on this point, yet to satisfy ourselves we visited all the farmers for some 20 miles 

 northwest of Grinnell to find but one who thought possibly he heard a noise in connection with the passage through 

 the air. It was surely accompanied by little or only imaginary noise at this point. 

 The train of smoke left by the meteorite seems worthy of notice. 



The velocity of the meteorite was such that its transit through the earth's atmosphere was momentary, and at 

 the time the head passed below the horizon the entire course of the meteor was marked by a broad ribbon of smoke, 

 having straight, sharply denned edges. This ribbon of smoke tapered off toward the higher atmosphere, as if vanish- 

 ing in perspective, showing the great rarity at that elevation. The smoke began to curl away gradually, but lingered 

 for a full 15 or 20 minutes before disappearing entirely. The fall was largely on unimproved land near Thompson, 

 covering with fragments an elliptical area some 2 or 3 miles long by 1.5 wide. (It seems as if the major axis might be 

 taken roughly as the direction of the meteor, that is, northeast, as it appeared to the eye; or, as Professor Winchell sug- 

 gests, the line of direction is more nearly that of the line of impact of the large fragments, that is, northwest.) 



The 66-pound fragment buried itself, close, to a farmer in the field, more than three feet in the hard prairie soil. 

 It was not dug out till the next day. Prof. N. H. Winchell, who visited the spot at once, states it was not hot when 

 dug out, notwithstanding all reports to the contrary, and that the clay around it was neither baked nor in any way 

 changed; and that the 86-pound stone fell on old turf, where last year's grass remained dry, and after the stone was 

 taken out, portions of the grass carried down by it, adhered to the surface unburned. Besides, one piece fell on a 

 straw stack and did not fire the straw. 



The paper of Torrey and Barbour is accompanied by township maps, showing the area 

 covered by the meteorites, also by drawings of the 66-pound stone and the microscopic appear- 

 ance of sections. The map shows that the fall took place in Linden and King Townships, north- 

 west of Forest City and Leland. 



Newton 9 observed lines of structure in polished surfaces which he described as follows : 



The polished surface of a small specimen of this stone, 3 or 4 sq. cm. in area, shows several hundreds of bright 

 metallic points. The larger iron particles in this area have great varieties of shapes, the smaller ones are usually mere 

 points. When seen with a lens, or even at a distance from the eye suited to distinct vision, there does not appear to 

 be any regular structure or arrangement of the bright points. But if the surface is so held as to be a little beyond the 

 point of distinct vision and at the same time turned around in such a way as to reflect always a -strong light to the eye, 

 either skylight or lamplight, there appear lines of points across the polished surface of the stone, which suggest very 

 strongly the Widmannstatten figures on metallic meteorites. At times as the stone is turned no lines can be detected. 

 Again, one set of parallel lines or two sets crossing each other become visible. Some of the sets are very sharply mani- 

 fested, and some are so faint as to leave one in doubt whether the lines are real or only fancied. There are on the 

 surface in question six or eight of these sets of lines. 



A second surface was ground nearly parallel to the first, at about 1 cm. distant from it, and like lines appeared 

 on this parallel surface. Some of the lines, but not all of them, corresponded in direction in the two surfaces. Four 

 more surfaces approximately at right angles to the first surface, and corresponding to the faces of a right prism were 

 then ground and upon these surfaces the like sets of lines appear with greater or less distinctness. 



These markings are such as we might expect if the forces which determine the- crystallization of the nickel-iron 

 of the iron meteorites also dominated the structure of the rocklike formations of the stony meteorites and the distri- 

 bution therein of the iron particles. The relation of quartz crystals to the structure of graphitic granite is naturally 

 suggested by these meteoric markings. 



Brezina, 7 in 1895, made the following observations: 



Forest is distinguished by the great number of complete individuals weighing from 40 kg. down, on which, as in 

 the case of Mocs and Pultusk, numerous formations, especially those due to fusion, are to be seen. Armor formation 



