352 lilt' Anii'i'ntl II (ifDlinjiKf. Iti'iriiil»i-, iHiii 
LalMari'. liut tlu' ^ppusilKja of Anijj(j. who was rliaiactcrizi'tl by 
Jj.aPlaoo as the -i^reat elector of the Academy. " This was a 
mortal blow and he faded away rai)idly on learnin<j: of it. for he 
had l>een duly iioniinate(l liy some of his scieiitilic friends in 
Paris. 
1 fain would dwell on the beauties of such a charactei'. It was 
an exotic plant, forcil)ly transferred from luxuriance to the com- 
parative desert and harshness of our northwestern frontier. It 
bloomed for a short time, disseminatini: unstintedly its fra<j;rance 
on the surrounding atmosphere, but the colds and common blasts 
of our unsuited social climate, though wholesome to the Ameri- 
can-bred spirit, were unfit to nonrisli liis (lelicateconstitution. and 
he drooped, faded and disapi)eared. leaving to us a remembrance 
of a Itright soul, a gleam of a i)uri' character. — a \\earied fire-fly 
struggling ill the tt'Uipest. a rose that wasted its fragrance on the 
desert air. 
GENESIS OF IRON ORES BY ISOMORPHOUS AND 
PSEUDOMORPHOUS REPLACEMENT OF 
LIMESTONE, ETC. 
Bv .I.vMKs I'. KiMiiAi.i., Wasliiiii;tcin. 1). ('. 
(ContiniU'd from the Auk ricmt Jounml nf Sr/< nrr, Vol. \iii, Sopt . IS'.tl.j 
Progressive studies of stratiform iron-ores throughout the 
geologic series of stratified rocks, have led to a wide — almost uni- 
versal — acceptance of explanations of their development as 
products of chemical transmutations, or epigenesis. So far as 
based on un([uestionable cliemical reactions, these exi)lanations 
(litter mainly as to their a|)i)lication to given occurrences of iron- 
ores. Wliat may be ternuMl the rej)lacement theory, has Iteeu 
held during the last decade to have a wide application, esju'cially 
on this continent, to iron-ores on horizons of originally ferrifer- 
ous limestone and other calcareous material. However, the appli- 
cation of this theory may be restricted from considerations of 
synchronous, or immediately successive, accumulations of the 
two kinds of matt'rial — calcareous and fcrrifeious. it will ob- 
viously be much tin- wider if it n)ay lu- believed tiiat replacing 
salts of iron are often from extraneous sources, and that tlu' i)ro- 
cess of replacement or cliemical interchange' is tlnougii circum- 
stances of atmospheric :\\m] top(igrai)liic. as well n> st latigi'aphic 
