234 MEMOIRS NATIONAL ACADEMY OF SCIENCES, VOL. XIII. 



Separate analyses of these gave : 



Si0 2 FeO MgO Na^O K and Li A1 2 3 



Soluble.... 35.61 27.20 33.45 1.45 trace 0.71 =98.40 



Insoluble.. 55.02 27.41 13.12 1.01 trace 0.84 =98.42 



This plainly shows that the principal constituent of the soluble portion is an olivine rich in oxide of iron, approach- 

 ing hyalosiderite in composition, and that the insoluble part is pyroxene. The nickeliferous iron contained, besides 

 traces of phosphorus, sulphur, and copper — 



Fe Ni Co Cu P S 



89.04 10.34 0.58 trace trace trace =99.96 



From an examination of an entire stone sent me after the completion of the above analysis, I have found the spe- 

 cific gravity to be 3.57. — Louisville, Kentucky, April 15, 1875, J. Lawrence Smith. 



The first stone from the meteor that was found was discovered lying on the snow on the afternoon of February 15, 

 and was adherent to snow and ice underneath. As the weather had been very cold from the time of the meteor-fall to 

 the time of finding this fragment, it must have been warm enough when it fell to slightly melt the underlying snow, to 

 which it was afterwards frozen. 



I visited the spot shortly afterwards and found that it had first struck the ground more than 30 feet to the southwest 

 of the place where it was found, making a slight indentation and bounding thence to the place where it finally came to 

 rest. It was a fragment and showed a secondary coating of rather more than average thickness. 



The other meteoric stones were not found until after the melting of the snow in the latter part of March. It is doubt- 

 less, owing to the frozen condition of the ground and the low angle of descent, that only a few of the larger pieces made 

 any indentation in the earth, and we may therefore suppose that a much larger proportion of this meteor-fall has been 

 secured than is usual. 



The velocity with which the meteor moved can not be satisfactorily stated. According to the data just given 

 the maximum would be about 10 miles per second, the minimum 3 miles. The most probable value for the last 60 

 or 70 miles of its course is from 6 to 7 miles per second according to the estimate of Mr. Christie, of Amana, who happened 

 to be walking rapidly at the time the meteor appeared and continued for a distance of fourteen paces, when, having 

 passed the corner of a building that threatened to obstruct his view, he stopped, and watching the meteor until it dis- 

 appeared, and gave his estimate of the whole time at 10 or 12 seconds; and as he saw it through 60 or 70 miles of its 

 path the resulting velocity would be as given above. 



Giimbel 8 described the meteorite as follows : 



On February 12, 1875, according to the statement of J. Lawrence Smith, in the State of Iowa, North America, 

 about 10.30 p. m., there fell from a slightly cloudy sky, with a loud report, a widely visible meteor, which left a large 

 number of stones. Smith estimated that not far from 150 kg. of stones were collected, of which 25 kg. came into the 

 possession of Professor Hinrichs. To his kindness the Academy (Munich) owes a splendid specimen of not far from 

 1,500 grams weight, which afforded the opportunity for the following more accurate description of the constitution of 

 this exceedingly noteworthy meteoric stone. 



The Iowa meteorite belongs to the very common class of stones ordinarily designated as chondrites, or, according to 

 Daubree, to the subdivision of Sporadosiderites and in the group of Oligosiderites, classified as Professor Hinrichs, in 

 the note accompanying a specimen of this stone sent to the Paris Academy, had already rightly noted and as Daubree 

 himself approved. 



The somewhat sharp-edged, acute-angled, irregularly tetrahedral stone is covered with a black fusion crust, is of a 

 light grayish-white color in the interior, and is supplied with numerous small black lumps and grains of meteoric iron 

 and iron sulphide, and occasional small specks of rust. The stone is quite hard and can not be pulverized with the 

 hand. It resembles in general character the meteoric stone of Pultusk, since like this, neglecting the meteoric iron 

 and iron sulphide, it consists of a whitish and yellowish groundmass in which isolated olivine grains with a glassy luster 

 appear, as well as sometimes darker, sometimes brighter, and occasionally opaque globules. Daubree compared it to 

 the meteoric stone of Vouille (May 13, 1831), and with that of Aumale in Algiers (August 25, 1865). By this fall the 

 number of chondrites, already greatly predominating over all other sorts of meteoric stones, was again increased by one 

 and the impression of the unitary origin of all these fragments from one former whole, which Meunier recently so 

 strongly emphasized, was materially strengthened. 



The exterior, sharp-edged, and angular form of the stones of this fall, which is but slightly obscured by the thin 

 superficial fusion crust, points unmistakably to broken fragments of a larger mass of stone, which was caused by the 

 shattering of an already fully prepared compact substance. That this dismemberment took place during the passage 

 through the earth's atmosphere, is indicated by Smith's observation, who stated that many of the stones which fell 

 looked as if they were freshly broken, and that the broken surfaces showed the beginning of fusion. There is, moreover, 

 no rounding off, no flattening out or streaking, or twisting like a rope, such as a softer, more pliable body furnishes in 

 moving upon a cosmic pathway or again such as it must receive in its flight from a volcanic eruption, like the papilli 

 and volcanic bombs. The inner rough-grained constitution, moreover, shows no trace of glassy or lavalike particles 

 which can not be made to correspond with a fusion of the mass by fusion-flame, and precludes all thought of a product 

 of eruption after the manner of our volcanoes. The outward form and inner constitution of this sort of meteorite speaks 

 accordingly, from the petrographic standpoint, against the supposition that these meteoric stones were cast out of the 

 earth as the product of a powerful volcanic eruption. It is equally improbable that they originated from swarms of 



