608 



• KNOWLEDGE • 



[May 19, 1882. | 



THE COMET. 



^pilIS wci'k wo give tlin comit'.s path (as computed \>y 

 A. Dr. E. Lamp, of Kiol), from May 18 to the end of the 

 month. As some correspondents wlio have eqnatorially- 

 mounted tchjscopos are not altogether content witli the 

 mere mafvpiiig of the path, though the comet can now Ije 

 readilj- seen in a good field-glass (we have seen it for the 

 last fortnight in one of Browning's Panergetic Glasses) 

 directed to its mapped jilace for the night, we append Dr. 

 Lamp's positions in right ascension and North Polar 

 Distance for the last half of May : — 



Dote. K.A. >• P.IX 



May 13 41 31 



15 56- 



M. 



1 5 14 16 2» 



1 27 .'iO 17 11 



1 18 5 18 3 



2 G 52 19 2: 



2 23 53 20 '.> 



2 39 14 21 2'> 



2 53 22 41 



3 5 21 24 S 



3 10 26 25 34 



3 26 24 27 6- 



3 35 20 28 41 



3 43 27 30 2a 



3 50 46 32 2 



3 57 24 33 47 



4 3 27 35 35 



4 8 57 37 25 



4 14 1 39 19 



4 18 39 41 15 



The perihelion passage will take place on or about June ItC, 

 midnight, at which time the comet's distance from the sun 

 will lie only 61 thousandths of the earth's mean distance. 



^ 



Chalcedony knxlosin'g Liquids. — I have read with much inteivsl. 

 the paper by the Rev. ilr. Wigt^ns on chalcedony enclosintj liquids, 

 in your issue of March 21. A specimen, such as he describes in- 

 the collection of Mr. Patrick Dudgeon, is referred to in Traill's 

 " Treatise on Quartz and Opal," 1870, where a considerable <|Uiim- 

 tity of water enclosed in the chalcedonic druse was lost by gradual 

 exudation through the crystalline pores during the course of years, 

 but which was partly restored. At Professor Hcddle's suggestion, 

 the nodule was immersed for a considerable time in water, under 

 the exhausted receiver of a powerful air-pump; the air was thus 

 exhausted from the interior of the nodule, and favoured the gradual 

 admission of water upon the restoration of the atmospheric pres- 

 sure. MiNEKALOGlST. 



The Fever Tree. — The Eucalyptus globulv.t, which is being in- 

 troduced in California, has many qnalities which recommend it to 

 Eastern sylviculturists. It comes originally from Australia, whei-e 

 the tests of various soils and varying seasons have amply demon- 

 strated the good qualities of the tree, and its rapid growth even 

 under adverse surroundings. Trials of late years in Southern 

 Europe have further verified these claims, and there is no reason 

 why the tree will not flourish in every section of the United States. 

 It is hardier than the chestnut, and, like the latter, it will grow in 

 the rockiest soils. It is more independent of rain food tlian any 

 tree known in this country, wet and dry seasons alike failing !<>• 

 affect its growth. Its wood is hard, somewliat of the r.utm*e of 

 yellow pine, but firmer and stronger, and fit for use in si>i]> 

 timbers, while in Australia cabinet-makers, wheelwrights, a>i«F 

 carpenters use it throughout their trades. The bark yields a 

 febrifuge second only in efficiency to quinine, but superior ia all 

 Tiiedical qualities to cinchona. This quality alone must make tlM*- 

 tree invaluable, and its cidture here, to an appreciable extent, would 

 settle for ever the vexed question of quinine duties. The rapidity 

 nf its growth is its most wonderful feature. It grows four times a» 

 fast as the American pine, and for all ordinary purposes is fit to rat 

 in five or six years. For the Eastern and Middle States, whore tbn 

 lack of forest protection is not infrequently felt, no tree has lx>»n 

 offered the culturist that can present so many primarv' points or 

 vantage as the Australasian immigrant, and its general introduction 

 and culture should only be a matter of but little time. It may be 

 added, the tree yields fragrance, but produces no fruit or nut. Its 

 beauty of form and luxuriant evergreen foliage are additionsl 

 qualities that must recommend it incountrvor city. — Frank Leslh'f 

 llluairated. 



