Aug. 11, 1870] 
NATURE 
395 
stitution of felspar, or if, indeed, its true nature can be 
represented by such formulae, is a question which Kolbe 
leaves untouched, for the simple reason that the necessary 
experimental foundation from which alone valid argu- 
ments can be drawn, is entirely wanting. 
Professor Kolbe concludes this remarkable paper by 
defining what should be the future aim of the student 
in Mineralogical Chemistry. He must not now rest 
content with a mere quantitative analysis, or with the 
empirical deduction of rational formule from the results 
of such analysis. Such a process can never fully elucidate 
the chemical constitution of inorganic compounds. This 
can only be accomplished by a careful and systematic 
study of the decomposition, syntheses, and substitutions ; 
in other words, by the application of methods of research 
similar to those which have yielded such splendid results 
in Organic Chemistry. T. E. THORPE 
NEW OBSERVATORY IN THE SOUTHERN 
HEMISPHERE 
ap t= following statement with regard to the Cordova 
Observatory, to the foundation of which we have 
before referred, is extracted from the last number of Silli- 
man’s American Fournal of Science and Arts. 
“The Argentine Congress voted to establish a national 
observatory at Cordova, at the instance of President 
Sarmiento, and through the exertions of the present 
Minister of Public Instruction, Dr. Avelleneda, who in- 
vited me to organise and take charge of it, knowing my 
desire to extend the catalogue of the southern heavens 
beyond the limit of 30° to which-the zones of Argelander 
extend. Bessel went through the region from 45° N. to 
15° S. with systematic zone observations at Kénigsberg, 
which have since been reduced and published in two 
catalogues by Weisse of Cracow. Argelander carried the 
same systematic scrutiny with the Meridian Circle, from 
Bessel’s Northern limit to the pole, and afterwards from 
Bessel’s Southern limit to 30° S. 
“Since then Gilliss has observed a series of zones for 
30° around the south pole; but the reduction of these, 
although very far advanced, was not completed at the 
time of his death, and the MS. is now stored somewhere in 
Washington. Let us hope that it may at some time be 
recovered, the work completed and given to the world. 
“My hope and aim is to begin a few degrees north of 
Argelander’s southern limit, say at 26° or 27°, and to carry 
southward a system of zone observations to some declina- 
tion beyond Gilliss’s northern limit, thus rendering com- 
parisons easy with both these other labours, and permitting 
the easy determination of the corrections needful for 
reducing positions of any one of the three series to corre- 
sponding ones forthe other. Itis of course impossible to 
arrange in advance the details of such an undertaking, 
but my expectation is to go over the region in question in 
zones 2° wide (except in the vicinity of the Milky Way 
where the width would be but one-half as great), up to a 
declination of about 55°, after which the width would be 
gradually increased as the declinations became greater. 
Within these zones all stars seen as bright as the gth 
magnitude would be observed, so far as possible, moving 
the telescope in altitude when no bright star is in the 
field until some one becomes visible, according to the 
well known method of zone-observations. 
“For reducing the observations, differential methods will 
probably be employed, inasmuch as the time now assigned 
for my absence from home would be inadequate for proper 
discussion of the correction required for nice determina- 
tions of an absolute character. Still, itis my present pur- 
pose, so far as possible, to make such subsidiary determi- 
nations as might hereafter be needed in any attempt at 
computing the observations absolutely. But as I hardly 
venture to anticipate any opportunity of making a thorough 
determination of the constants of refraction, or of the 
errors of graduation, it seems best to arrange for a 
differential computation at least at first. 
“Jt is improbable that a sufficient number of well-deter- 
mined stars will be found available even for this differential 
reduction, and the necessity may thus be entailed of 
determining the comparison-stars myself, this determina- 
tion, however, itself depending upon standard star places. 
So far as possible I propose employing those heretofore 
determined by me, and published by the Coast Survey, 
which form the basis of the star places of the American 
Nautical Almanac. 
“With these observations of position it is my hope to 
combine others of a physical character to some extent ; 
but in the presence of a plan implying so much labourand 
effort, it would be unwise to rely upon the possibility of 
accomplishing much more than the zone-work. 
“The meteorological relations of the place are very 
peculiar, but I dare not undertake any connected series 
of observations bearing upon these, without self-registering 
apparatus, which is beyond my means. 
“Cordova is one of the oldest cities, and contains the 
oldest university, of the Western hemisphere. It is 
situated in 313° S. latitude, on the boundary of the Pampa, 
where the land begins to rise toward the group of moun- 
tains known as the Sierra de Cordova. It is connected 
with Rosario, on the Parana, by the Central Argentine 
Railway, which has probably been already opened to travel 
through its entire length of about 250 miles, although 
information to that effect has not yet reached this 
country. 
“The two largest instruments will be a Repsold meridian- 
circle of 54 inches focal length and 43 inches aperture, 
and an equatorial by Alvan Clark and Sons, provided with 
the 11-inch object-glass, by Fitz, lately in the possession 
of W. Rutherfurd, who has supplied its place by one of 
13inches, A photometer by Ausfeld of Gotha, according 
to Zdllner’s latest form, has been constructed under the 
supervision of Prof. Zéllner himself ; a spectroscope will 
be furnished by Merz of Munich, and a clock by Tiede of 
Berlin. 
“The Scientific institutions of the U.S. have afforded the 
expedition every possible assistance. The Coast Survey 
lends a circuit-breaking clock, a chronograph, and a 
portable transit; the Smithsonian Institution lends a 
zenith telescope; the American Academy of Arts and 
Sciences of Boston (probably) a photometer and spectro- 
scope ; the Washington Observatory and the Nautical 
Almanac have greatly aided the undertaking by gifts of 
books and by a manuscript copy of Gilliss’s catalogue 
of Standard Stars ; and from the astronomers of England, 
Germany, and Russia important assistance has been freely 
and effectively contributed, in the order and supervision 
of instruments and apparatus, and by the gift of books, as 
wellas by important and valuable suggestions. 
“Four assistants will accompany me, Messrs. Miles Rock, 
John M. Thome, Clarence L. Hathaway, and William M. 
Davis, jun. We hope to reach Buenos Ayres not later 
than the middle of August. 
“The building is now under construction in Boston. The 
means available proved inadequate for its construction 
according to the original plan, which was in the form of a 
cross, with four square rooms about its centre, and turrets 
at its four extremities. One half of it will be first erected, 
and it is hoped that the remaining portion will speedily 
be added.” B. A. GOULD 
SCIENTIFIC SERIALS 
THE greater part of the Revue des Cours Scientifiques for 
July 23, is occupied by the commencement of a very able paper 
read before the Anthropological Society of Paris by Prof. Broca, 
on the Transformation of Species. Commencing with the pre- 
Darwinian theories of transformation of Blainville and Lamarck, 
| he then proceeds to give a résumé of the theory of Darwin, and 
