600 Dr. Walter Flight — History of Meteorites. 



during its solution in acid. In calculating the results of his 

 analysis he considers the sulphur to be combined with a portion 

 of this iron in the form of magnetic pyrites, and the remainder 

 of that metal to be alloyed with some of the nickel, the excess 

 of the nickel above that required to form the normal alloy being 

 present as oxide. As, however, it has not been shown to be a com- 

 ponent of the silicate, and recent researches (see page 315) have 

 failed to prove that it forms a constituent of meteoric olivine, it may 

 be present as alloy. If we exclude the oxygen of this nickel oxide, 

 the ratio of the oxygen of the silicic acid to that of the total bases 

 of that portion is 13-35 : 13-43, from which it appears that the chief 

 constituent of the Ornans meteorite is an olivine having the 

 formula 2 ($ Mg f Fe) Si0 4 . 



Tschermak finds that the dull grey colour of this stone is due, at 

 least in part, to the presence of carbonaceous matter. (Compare 

 with Goalpara meteorite, page 605'.) 



1868, September 7th. — Sauguis-St.-Etienne, Canton de Tardets, 

 Arrondissement Mauleon, Basses-Pyrenees. 1 



At 2-30 a.m. a meteor emitting a pale green light traversed the 

 sky over Mauleon, and broke up leaving a faint whitish cloud which 

 lasted for some time. Its disappearance was succeeded by a noise as 

 of thunder, followed by three or four loud detonations, which were 

 heard over an area 80 kilometres wide. The inhabitants of Sauguis- 

 St.-Etienne heard, in addition to these noises, a sound like that pro- 

 duced by quenching hot iron in water, and a dull thud caused by 

 the meteorite striking the ground. It fell about 30 metres from the 

 church in the bed of a small stream, and was so completely shattered 

 that the largest fragments did not measure more than 5 cm. in length ; 

 their total weight is about 2 kilog. The fall was witnessed by two 

 men, who, returning home late, had continued in conversation at the 

 door of one of their dwellings. Frightened by the hissing noise, 

 they fell on the ground, and saw the stone strike the earth about 

 20 metres from them. 



The Sauguis meteorite consists chiefly of rocky matter, the metallic 

 grains being small and sparsely distributed ; troilite is noticed in 

 nodules, some of which are 10 mm. across. The crust is dull black 

 and possesses the unusual thickness of 1 mm. ; the fine black veins 

 observed to traverse certain meteoric rocks are abundantly present 

 in this stone. A microscopic section was found to act strongly on 

 polarised light, and to have the appearance of a breccia of very 

 small transparent and colourless particles. 



Daubree finds the rock composing this meteorite to be identical 

 in all respects with that forming the stones which fell at Villanova 

 di Casale in Piedmont (1868, February 29th) [see page 596] ; a 

 practised eye examining specimens of these two falls would fail to 

 distinguish one from the other. 



1 G. A. Daubree. Compt. rend. 1868, lxvii. 873. — S. Meunier. These presented 

 a la Faculte des Sciences de Paris, 1869. Recherches sur la Composition et la Struc- 

 ture des Meteorites, 16. 



