Notes and Memoranda. 79 



maculated with oolong spots of orange, red down the centre. Dorsal cirri re- 

 flexed purple, with faint reddish tinge. 



Iodine Dissolves Gold. — M. Mckles states, in Comptes Hendus, that if 

 iodine, water, and gold leaf, are heated in a tube to 50° C. (122° F.) the gold is 

 dissolved. Ether may be substituted for water, and the action will take place on 

 exposure to strong sunshine. The filtered solution deposits a film of gold on 

 evaporation, if the heat at the end of the operation is sufficient to decompose the 

 iodide of gold which is deposited. Sesqui-iodides and bromides of iron likewise 

 dissolve gold. 



Size and Life oe a Mammoth Tree (Sequoia gigantia). — M. A. De Can- 

 dolle, giving an account to the French Academy of the recent Botanical Congress 

 in London, stated that an exact measurement of one of the mammoth trees of 

 California, the " old maid," which was blown down in a storm a few years since, 

 had been made by Mr. Edmond De la Kue. It was found to be twenty-six feet 

 five inches and nine lines, six feet above the ground. Mr. De la Hue traced the 

 annual layers on a sheet of paper which M. de Candolle exhibited, and it was 

 found that the layers amounted to 1234. 



Yolcanic Emanations and Disease.— M. de Corogna states to the French 

 Academy that in districts towards which the winds blow the gaseous matter given 

 off by the eruption at Santorin, inflammations of the eye, bronchitis, and digestive 

 derangements have been frequent, while other districts have not suffered in the 

 same way. Asphodels, and generally, plants of the lily tribe have been injured. 

 He ascribes the human maladies of indigestion, etc., chiefly to sulphuretted hydro- 

 gen, and the vegetable disorders to hydrochloric acid vapours. The ophthalmia is 

 traceable to volcanic dust. 



The Zodiacal Lio-ht. — M. Liandier has a note in Comptes Hendus stating 

 that for several years he has watched the zodiacal light during the evenings of 

 February and March. This year, for the first time, he saw it on the 19th of 

 January, and watched it till the 5th of May. He considers it to have the shape 

 of a perfect cone, varying in luminosity and colour from dull grey to silvery white, 

 the changing aspect probably being occasioned by the condition of our atmo- 

 sphere. In February the summit of the cone reached the Pleiades, and the Twins 

 in May. Between January and May he found it to follow the zodiacal movements 

 of the sun. He believes the luminous cone to be a fragment of an immense 

 atmosphere enveloping the sun on all sides. If so, he Bays it may be expected 

 to exercise an enormous pressure on the sun, with great development of heat ;. 

 and if local variations occur, he thinks they may explain the occurrence of spots 

 through the reduction of temperature that would follow diminished pressure. 



Effects of Increase of Sun's Mass.— On the 1st September, 1859, Mr. 

 Carrington and Mr. Hodgson witnesssed a sudden blazing up in the sun, which is 

 supposed to have indicated the fall of an extraneous body into our luminary, and 

 a consequent accession to his mass. In Monthly Notices, vol. sxvi., No. 8, 

 recently issued, will be found a mathematical paper computing the effects of the 

 fall into the sun of such a body as our earth, which some persons suppose would 

 produce such ablaze as to scorch up all the planets. Mr. Waterston finds that 

 if the blaze so occasioned were persistent, the general rise of temperature would 

 not exceed 10 3 or 15°, but he observes that as soon as the falling body had 

 plunged below the atmosphere into the fluid incandescent body of the sun, the 

 blaze would terminate, though the temperature of that part of the sun would be 

 sensibly increased. If the whole potential radiating power of the sun were 

 increased 1000°, he says, " even this is Gtaly one twelve-thousandth part of the 

 potential temperature that sends heat to us sufficient to maintain a general average 

 temperature over the surface of the earth of about 500° above the absolute zero 

 of space. Now this proportion of 500° is only one twenty -fourth of a degree, and 

 this is the extreme maximum effect that can be reasonably expected from such a 

 planet fall." But increase of the sun's mass would shorten the year, and the addition 

 of matter equal to our globe would effect this to the extent of 130", causing a 

 difference in the longitude of the sun at the end of the first year equal to 5"*3. 



