z^ecnstein l^onnation una aas Komaec^i^nu,^ , "j -- 

 NiTz, Leipzig. 13 pp. 4to, and 23 plates. Leipz'g' 

 otice).-In the former mention of this work (vol- 

 5 of the objections were stated to the substitution ol 



sing water, &c. The whole mixed gaseous fuel can evolve 

 about 4000" in the furnace, to which the regenerator can return about 

 3000° more:'~Pkil. Map., Aug., 1862. 



[The readers of this Journal will remember ray description of the fur- 

 naces of Moses Thompson for the combustion of wet fuel, (this Journal. 

 [2], XXX, 243). The chemical reactions and many essential points ot 

 construction in the two cases are quite identical — the slow combustion of 

 the wet fuel in an anterior furnace very imperfectly supplied with air— 

 the reaction of the vapor of water with the carbonaceous gases in the 

 mixing chamber— the intense heat therein produced by these reactions- 

 the low temperature of the smoke stack are all features of siroilanty, 

 while the alternate use of the combustion chambers supplied a species of 

 regenerator, in fact, if not in name. If Mr. Siemens has not seen Mr. 

 Thompson's plans and specifications, or my description above referred to, 

 he will find in them another proof of the old adage that "there is notbmg 



11. GEOLOGY. 

 1. Dyas, oder die Zechstein Formation und das Eothliegende ;^hy Dr. 

 Hanns Bruno Geinitz, Leip 

 1861. (Second : " ~ 



xxxiii, p. 425) some of the objections were stated ' 

 "' " I Dgas for Permian in geology, and a further v 

 the volume was p • ' • -• '- — 



yet received the promised 



bearing on the question of the ( 

 leads us to give without delay i 

 pared by Mr. A. Schott. The 



the question as to whether the Permian .„ ^ - , -^ 



relations— the former being the view now generally held by S^^^°f 

 and sustained by Dr. Geinitz. The work is illustrated by many piaw^ 

 admirable in lithography as well as in accuracy of drawing. 



Since 1848 the zoological species of the Permian or "Dyas" have bee 

 increased to thrice the original number. This recent work by Dr. W 

 nitz contains descriptions of 216, some of which are new. All tbe sp 

 cies hitherto described and known to the author are included. . 



After extensive study, and a close scrutiny of the fossils, Dr. ^ein> 

 states that the principal leading forms of the formation (the Zeclist ; 

 belong to types that are especially characteristic of the Palaeozoic ei , 

 although some older types, as for instance Trilobites, had disappeared 

 during the preceding Carboniferous period. ..a 



The tribe of Saurians, the Russian species excluded, are represent^ 

 by 9 or 10 species, among which are Lacertians and Labyrinthodon^j 

 the latter appear for the first time during the Carboniferous age »" 

 reach their highest development during the Trias. , -j. 



Of Fishes, 43 species are described, among which keterocercal g^'^^^'^^ 

 prevail, and no homocercal species occurs. The smooth-scaly speci^s 

 Palceoniscus of the "Rothliegende" and Acanthoides gracilis here pro 

 the relationship of tbe formation with the Carboniferotfs. 



