Literary Notices. 231 



Miscellaneous. — Staining of Wood. — The aniline dyes are 

 now, with excellent results, applied to the staining of the softer 

 woods, so as to impart to them the appearance of the more valuable. 

 And the process is the more satisfactory, as the wood is coloured 

 throughout its whole substance. To effect this, the air is exhausted 

 from the pores of the wood, after which the aniline dye is injected. 



Production of Blacks by the Daguerreotype Process. — The blacks 



ordinarily produced by the daguerreotype picture are merely nega- 

 tive ; that is, they are due simply to the absence of light, which is 

 reflected away from the eye by the polished surface. Some time 

 since it was found that they might be obtained by acting on the 

 sensitized plate with two complementary colonrs in succession. 

 More recently, M. Niepce de St. Victor has discovered a means of 

 producing them at once, and by a simple process, that consists in 

 plunging the plate, which has been prepared as for the production 

 of the natural colours of objects, into a bath, formed with fifty 

 centilitres of alcoholized soda to one hundred grammes of water, con- 

 taining a very small amount of common salt ; raising the temperature 

 to 60° Cent., and keeping the liquid, which is to be constantly stirred, 

 at that temperature for a few seconds ; then taking out the plate, 

 rinsing it well with water, and heating it. The slight reduction 

 of the chloride of silver which has taken place will have given the 

 plate a violet blue tint ; and if it is now covered with a varnish 

 consisting of dextrine and chloride of lead, it will afford blacks 

 along with the other colours. There are modes of intensifying the 

 blacks thus obtained, but they are attended with certain incon- 

 veniences which render their application not desirable. 



LITERARY NOTICES. 



Descriptive Astronomy. By George F. Chambers, F.R.A.S., of 

 the Inner Temple, Barrister-at-Law. Oxford, at the Clarendon 

 Press. — A few years ago, Mr. Chambers brought out a book on 

 Astronomy, and the present work, though not so acknowledged in 

 the title page, is a second and enlarged edition of the first one. 

 Any one taking up the book, and led by the title page and preface to re- 

 gard it as a new one, and discovering on examination that it is simply 

 an improved edition, would consider that he had not been treated in 

 the usual straightforward way, and we cannot but regard it as a 

 mistake in so respectable a firm as that of Messrs. Macmillan and 

 Co., to have permitted Mr. Chambers to give a fallacious aspect to 

 his really useful compilation. Taking the book altogether, it will 

 be found very useful for amateur observational astronomers, as it 

 brings together, in a compact form, a considerable range of inform- 

 ation constantly required in private observatories. The plan is, 

 first to describe, in a brief manner, the sun, and the larger planets, 

 then follow chapters on eclipses of various kinds, transits of the in- 

 ferior planets and occupations. " Physical and Miscellaneous Astro- 

 nomical Phenomena" occupy several chapters. Comets receive notice 



