840 General Notes. [ October, 
of Catonia, recently collected some dust which fell in Sicily, and 
found it to contain not only metallic iron, but also nickel and 
various silicates and phosphates, such as are commonly found in 
meteoric stones. He is, therefore, inclined to believe either that 
the dust has been abraded from meteorites, or that it circulates in 
space, and is attracted to the earth’s surface when it penetrates 
within the atmosphere. 
Professor Tacchini, who has exchanged the observatory of 
Palermo for that of the Collegio Romano, in Rome, has recently 
published a lengthy memoir entitled “ Sulle polveri meteoriche 
di Scirocco raccolte in Italia e segnatamente in Sicilia.” He was 
assisted in his researches by Professors Macagno and Ricco, and 
a résumé of the results at which they arrived; was recently read 
before the meteorological section of the French Association for 
the Advancement of Science at Algiers. The memoir contains 
some beautifully-executed microscopic drawings of the appeat- 
ance of the meteoric dust when highly magnified, and by a series 
of small maps showing the barometric curves for the periods 
during which the dust fell. * * * A notable feature revealed 
by the analysis, was the similarity of the composition of the dust 
collected from various localities and at different epochs. = 
A microscopic analysis revealed the presence of transparent ahr 
opaque polygonal crystals, black granules of metallic iron, and Pe 
magnetic oxide of iron, feldspar, carbonate of calcium and sane; 
various vegetable substances and spores were observed, Palmella 
cruenta, Protococcus nivalis v. pluvialis and Discerea purpurea 
Professor Tacchini considers that the dust is of terrestrial orig!” 
and that it is brought from the Sahara, being raised into the 
higher regions of the atmosphere by cyclones and whirlwinds, 
where it may remain suspended during transport for several oa 
A barometric depression invariably accompanies the fall of the 
dust.—G. F, Rodwell in Science Gossip. 
MIcRoscopy IN THE AMERICAN ASSOCIATION FOR THE ADVAN 
MENT OF SCIENCE.—At the meeting of the American Aasshcio 
for the Advancement of Science, held recently in Cincinnati, Me 
sub-section of microscopy had several important and interes 
sessions, at which a number of valuable papers pertaining oe 
science of histology and the zechnique of microscopy were aa 
sented. Rev. A.B. Hervey, of Taunton, Mass., was chairman, an 
Professor Wm. H. Seaman, of Washington, was secretary. ai 
In the reorganization of the American Association, which " 
perfected at the Cincinnati meeting, the full section of “ Histology 
and Microscopy” was established, by which this was put se 
footing of equality with the other departments of science repr of 
sented in the Association. By this arrangement the chairman ¢ 
the section becomes a vice-president of the Association, and in 
together with the secretary and a fellow elected by the yas 
represent the section in the standing committee. It 1s belie 
NCE- 
