88 PROCEEDINGS OF SECTION B. 



Professor Liversidge, in 1902, published a most comprehensive 

 and valuable paper on " Meteoric Dusts, "^ on p. 283 of which he 

 shows that the presence of nickel and cobalt in such dusts has no 

 particular significance as an indication of cosmic origin. 



A paper by T. L. Patterson, entitled " Recent Dust Showers "^ 

 gives an interesting account of dusts collected by melting surface 

 snow, and of certain curious fused spherules, some of which consist 

 of silicates and others of magnetic oxide of iron, which occur in 

 the smoke emitted by factory chimneys, and which were found by 

 Mr. Patterson in the dust recovered from snow collected in the 

 vicinity of a manufacturing town. Both kinds of spherules occur 

 freely in the flue dust of factories burning coal, and when found in 

 atmospheric dust those of magnetic iron oxide might, without this 

 knowledge, be readily attributed to a cosmic source."' 



In 1901 Professor Hartley and H. Ramage published an 

 account of a careful spectroscopic examination of a large number 

 of dusts from various sources,* having special reference to the 

 presence of small amounts of nickel and the rarer elements. One 

 of the most striking features of this research was the demonstration 

 of the constant presence of minute quantities of nickel and other 

 rare metals in dusts from the most varied terrestrial sources. The 

 composition of the sooty particles which form a conspicuous con- 

 stituent of much of the atmospheric dust of our cities is fully dealt 

 with by Professor E. Knecht in a paper published in 1905.^ 



I exhibit samples of the Victorian and Sydney dusts and of 

 leaves incrusted with the latter, also volcanic dusts from eruptions 

 of Mounts Pelee and Vesuvius. 



9.— NOTE ON THE FREEZINCx POINT OF MILK. 

 By J. B. HENDERSON, Brisbane. 



Since reading a paper before this Section of the Australasian Asso- 

 ciation for the Advancement of Science at its meeting in Brisbane 

 (1909), the determination of the Freezing Point of all doubtful 

 samples of milk has been continued in the Government Chemical 

 Laboratory, Brisbane. 



The reading of that paper resulted in such a large number on 

 enquiries from all quarters that I thought a note on the results of 

 another two years' experience with the method might be acceptable 

 to public analysts. 



1 Proc. Royal Soc. N.S.W., XXXVI., 241, 1902, and Chem. News, LXXXVIU., 16 etc., 1903. 



2 Illustrated Science Monthly, July, 1884. 



3 See also Brit. Assoc. Adv. Science Reports, various volumes, 1881 to 1889, under " Meteoric Dust." 



4 Chemical Nerns, LXXXIII., 157, 1901. 



5 Chem. News, XCI., 259, 1905. 



