Notes and Memoranda. 467 



Atmospheric Currents and Shooting Stars. — M. Cliapelas, in a paper 

 read before the French Academy, alleges grounds for believing that the niove- 

 ments of shooting stars are effected by atmospheric currents occurring in the 

 higher regions to which our air extends ; and he considers that these bodies may 

 act like weathercocks and anemometers, giving us information concerning the 

 direction and force of the winds that influence their proper motions. 



Bacteeiums and Tyehoid Peter. — Professor Sigri calls the attention of 

 the French Academy to the presence of these infusoria in the blood of a man who 

 died of the above fever in the hospital of Sienna. This fact is very curious, taken 

 in connexion with the researches we have previously published (Intellectual 

 Observer, October, 1863, page 177) . 



Kiechhopp on Sun Spots. — The memoirs of the Berlin Academy contain M. 

 Kirchhoff's papers, of various dates, on the Solar spectrum, and it appears that 

 he attributes sun spots to a cooling action exerted by clouds which obstruct the 

 radiation of heat from the solar surface (which he imagines incandescent) , and thus 

 reduce a portion of the atmosphere immediately over the cloud to a temperature 

 below the point necessary to render it luminous. The spots, according to this 

 hypothesis, are portions of solar atmosphere cooled below red heat, and above 

 them, portions which have been cooled somewhat less constitute the penumbra. 

 It may be doubted whether this explanation will be found to fit the actual pheno- 

 mena. Such coolings would cause powerful and peculiar currents. Do exactly such 

 currents occur as would result from M. Kircnhoff's supposition, and are they 

 evidenced by the behaviour of the spots ? 



Distance op Sirius. — As Sirius now forms a magnificent object in our 

 heavens, we transcribe from Cosmos a few interesting remarks by M. Camille 

 Plammarion, who says, " thanks to the labours of Sir John Herschel, we know 

 that the absolute intensity of the light of Sirius has been estimated at 224 times 

 that of the sun, and that its parallax, amounting to 0"'23, gives for its' distance 

 from the earth the probable number of 52 billions of leagues. It follows that we 

 do not see the Sirius of to-day, but of twenty-two years ago : the ray of light 

 that we receive to-day having been emitted by the star about 1840." 



Azulene. — Mr. Septimus Piesse has discovered a substance to which he has 

 given this name, in several "ottos," or essential oils. It is a blue liquid, and 

 produces a blue vapour on ebullition. It is soluble in fatty and volatile oils, and 

 in most liquids except water. It bears a temperature of 700° or 800° F. in a sealed 

 tube without alteration, and only the strongest chemicals, with the aid of heat, 

 effect its decomposition. Sir D. Brewster reports that two blue oils containing 

 azulene — Matricaria chamomilla and Achillea millefolia — absorb the light between 

 lines A and B of the spectrum more powerfully than in the portions adjacent to 

 them. Blue otto of chamomile yields one per cent. ; otto of wormwood three 

 per cent., and otto of patchouli six per cent, of azulene. 



Mr. Highlet's Lantern Polariscope. — Mr. Samuel Highley has just 

 introduced a form of polariscope easily used with a magic lantern, and capable of 

 producing a variety of beautiful and startling effects. The light is polarized by 

 reflection from a bundle of glass plates placed at a suitable angle, and the general 

 arrangements are sufficiently simple and economical to be of wide use both for the 

 purposes of instruction and entertainment. 



M. Pasteur on Wine-making-.— M. Pasteur finds that grape-must does 

 not contain oxygen gas in solution, but only carbonic acid and nitrogen ; that if 

 the must is left in contact even with a large surface of air it does not oxydize, so 

 that until fermentation begins, it contains only carbonic acid and nitrogen ; but 

 the oxygen of the air combines with it in proportion to its dissolution with 

 oxydible principles naturally contained in grape juice. The combination of the 

 oxygen is not, however, so rapid but that we may find the gas in solution some 

 hours after the must has been agitated in contact with air. The oxydation 

 modifies the colour of the wine, giving the yellow tint to the juice of white grapes, 

 and browning that of the red, and it also appears connected with the formation of 

 the ether of wine. Gruy Lussac showed that oxygen was necessary to the fermen- 



