METEORITES OF NORTH AMERICA. 191 



in sec. 23, R. 49, T. 150, a stone was found which had embedded itself in the sod a few inches from the force of its fall, 

 the impact of the mass having also turned back the turf in all directions around it. There being no drift bowlders in 

 the region on the surface, this was at once connected with the rumbling noise. On examination it proved to be a 

 chondritic meteoric stone. Its weight was about 9.5 pounds and it was entirely covered with the usual black crust. 

 This being the first meteorite known to have fallen in the State, it is proposed to name it Minnesota No. 1, with a view 

 to continue the series by suitable numeration for all future Minnesota meteorites. 



In his 1895 catalogue Brezina 2 classified Fisher as an intermediate chondrite. About a 

 year after his first mention Winchell 3 gave a full account of the meteorite as follows: 



The stone is covered with a thick brown crust showing the wavy fluidal surface, indicating fusion by the applica- 

 tion of heat to the exterior. It is pitted with the usual depressions and prominences. Of the two pieces that fell, one 

 was immediately broken up by the farmers, who desired, as they said, to know whether any gold was inside of it. The 

 fragments were scattered amongst them and some were taken into North Dakota. The other stone remains entire. 

 The one which was broken up was the larger of the two, the smaller one weighs about 9.5 pounds. Several of the pieces 

 of the larger mass have been recovered and from these this description was written, except as to the exterior appearance, 

 which is described as it occurs on the smaller mass. The coating, however, on the smaller fragments has no noticeable 

 difference from that on that of the unbroken mass. 



The specific gravity of the stone is 3.44. 



The color is light gray, but flecked with rustiness from oxidation of the iron. The iron is not abundant, but is found 

 in isolated grains varying in size from a mere speck to 1.5 or 2 mm. in diameter. The broken surface glitters with scat- 

 tered bronzy reflections, apparently of troilite. 



In thin section the stone, aside from the iron elements, appears to be principally a granular mass of olivine more or 

 less rusted, and of enstatite, showing occasionally the chondritic structure. The olivine seems to have been entirely 

 shattered from its crystalline integrity and to exist now in the form of more or less angular cleavage and other fragments 

 impacted together and held in place by a secondary cohesion. Still, in general, the individual fragments are not far 

 removed from their original positions, and in some instances are sufficiently large to operate on with convergent light 

 with crossed nicols. 



The polarization colors are high. Of the numerous sections afforded by the slices some are found perpendicular to 

 the different axes of elasticity. In one perpendicular to ng(c) two cleavage systems are distinctly apparent which 

 intersect each other at right angles, although these are crossed by other coarse cracks which cut the grain into many 

 irregular fragments. These cleavages are those parallel to the brachypinacoid (010) and the base (001), the latter 

 being less evident than the former. Extinction takes places parallel to these cleavages. 



Another section is cut perpendicular to nm(b) and has a bright bluish-green color. It extinguishes parallel to its 

 principal cleavage (010), the other cleavage being reduced by the shattering which all the grains have suffered to an 

 irregular series of cross fractures of the lamellse 010, hardly continuous enough to be recognized as cleavage. This 

 section is parallel to the base. Other basal sections show no basal cleavage. 



Another section with two distinct rectangular cleavages is perpendicular to np(a), which in olivine indicates a 

 section parallel to the brachypinacoid. One cleavage is straight and clear, the other coarse and somewhat irregular. 

 Extinction is parallel to these cleavages. 



There are numerous sections which have extinction at a varying angle with the cleavage owing to their obliquity 

 with the principal zones. 



The chondri are composed of olivine and enstatite. The various lamellse consist of many individual granules 

 having a common orientation and the lamella? themselves extinguish in unison and frequently parallel to their elonga- 

 tion. Occasionally a granule not exactly in line with the series constituting one of the lamellse, but rather between 

 two lamellse, extinguishes at a different angle. The lamellse in the olivine chondri are nearly straight and parallel. 

 Between them is sometimes an isotropic substance which is probably glass, but sometimes this substance affords an 

 aggregate polarization. In those olivine chondri in which the lamellse are cut parallel to 001 — that is, perpendicular to 

 the mean axis of elasticity — the distinct cleavages run directly transverse to the elongation of the lamellse as viewed. 

 Hence the lamellse are of the nature of plates parallel to 100. Sometimes the lamellse contain no interlamellar glass, 

 but the alternate lamellse are differently oriented, there being two directions, with an angle of about 24° between them. 

 Sometimes parts of different chondri are closely adjacent, each having its independent orientation. In this condition 

 the appearance somewhat resembles the radiating lamellse of the chondri of enstatite and in some of the enstatite 

 chondri olivine constitutes a portion of the interlamellar mineral. 



There are apparently two isotropic substances in this meteorite, one being glass (at least glassy) and the other having 

 a cleavage. The latter is clear as glass in ordinary light and has refraction approaching that of olivine, as shown by the 

 shagreen which is produced on lowering the condenser. It may be maskelynite, which is a mineral discovered by 

 Tschermak in 1872, isotropic but having nearly the composition of labradorite. A sketch shows the aspect of the 

 cleavable grain in common light with the condenser lowered. This indeed is the only grain of the isotropic substance 

 showing a distinct cleavage. The noncleavable substance appearing like glass is rather widely distributed, but there 

 is no certainty that they are the same, although the glassy substance seems occasionally to transmit a little light between 

 crossed nicols. The cleavable mineral has occasionally a trace of a second cleavage. 



There is this distinction between these isotropic substances, viz, the glassy grains, as appears in the chondri of 

 olivine where the interlaminations between the lamella? of olivine are in part of this glassy substance, on becoming 



