Chemistry and Physics. 535 



own language the most philosophical work on chemistry which 

 the nineteenth century has yet produced. G. f. b. 



5. Manual of Chemical Technology, by Rudolf von Wagner, 

 translated and edited by William Crookes, F.R.S., from the 

 thirteenth enlarged German edition as remodelled by Dr. Ferdi- 

 nand Fischer. 968 pp. large 8vo, with 596 illustrations. New 

 York, 1892, (D. Appleton and Co.). — Wagner's Chemical Tech- 

 nology has so long been a standard work of reference, both in the 

 original form and in the English translation, that it hardly seems 

 to call for new commendation. The present edition, however, is 

 substantially a new work and has many excellent features of mat- 

 ter and arrangement due to the present editors. The last edition 

 prepared by Wagner himself was the eleventh, published shortly 

 before his death in 1880. In the latest (13th) German issue, a new 

 and more logical arrangement of the subject-matter has been 

 adopted, many new subjects have been introduced and others 

 have been thoroughly revised. Thus it is stated that, as compared 

 with the eleventh edition, more than half the text and illustrations 

 are new. The former English edition appeared twenty years 

 ago; the present one is based upon the 13th German edition, and 

 the English editor has made various minor modifications, and 

 added many explanatory notes, bibliographical references, etc., 

 to adapt it to home conditions. 



The book is rich in valuable information in every branch of 

 chemical technology and is indispensable to all interested in this 

 field. 



6. Laboratory of Chemistry, by J. E. Armstrong and J. H. 

 Norton. 144 pp. 8vo. New York (American Book Company). — 

 This is a useful little book detailing 164 experiments to be per- 

 formed by the student in the laboratory. The experiments are 

 well selected and described with sufficient fulness ; with the aid 

 -of a competent teacher they should give good results. 



7. Untersuchimgen uber die Ausbreitung der elektrischen 

 Kraft von Dr. Heinrich Hertz. 294 pp. 8vo, Leipzig, 1892. 

 (Johann Ambrosius Barth.) — It would be difficult to find, in the 

 recent literature of the subject of Physics, contributions more 

 distinctly " epoch-making " than those of Hertz, carried on through 

 the last five years, on the production and propagation of electri- 

 cal waves. These papers discuss, in a word, the production of 

 electrical waves by the oscillatory electric discharge, as of an 

 induction coil ; their propagation through the ether ; reflection 

 from metallic surfaces; refraction through non-conductors; inter- 

 ference, polarization, and in fact all the phenomena characteristic 

 of light waves, to which indeed they correspond although relatively 

 of enormous length. By them Maxwell's theory in regard to the 

 mutual connection between electrical and light phenomena has 

 received the most signal confirmation, and new directions for ex- 

 periment and theory have been opened out in which other workers 

 also have gained, and are gaining, important results. The original 

 papers have been for the most part published in Wiedemann's 



Am. Jour. Sci.— Third Series, Vol. XLIII, No. 258.— June, 1892. 

 35 



