* 
Miscellaneous Bibliography. 143 
14, L’ Unita delle Forze Fisiche Saggio di Filosofia Naturale. Del P. 
Anezto Secent, D.C.D.G. 511 pp., 8vo. Roma, 1864.—The principal 
object of this work, as stated by the author, i is to present to Italian read- 
ers an adequate representation and exposition, in their own language, of 
the modern doctrine of the u nity or padi oo! of natural forces, and 
of the principle of conservation of en energy. e style is professedly adap- 
quaintance with the literature of modern science. Though there is little 
that 1s absobut utely new in it, the book is valuable and interesting, bein 
a8 It 1s an able exposition of principles which may almost be called the 
the subject of modern physics. There is probably no book in which 
2 foe 18 more fully and satisfactorily treated than in this. The au- 
hi Y appears to us to do but scant justice to Mayer, to whom the whole 
SuDdJect is so iy inebied bess he does not even — him in the 
ey where are cited the names of those who hav ed mos 
oh is each of stew sad: re makes subsequently sie slight reference 
discoveries, 
les ond ord de M. chreseineh Préfet de la Seine, et executée sur la carte 
i ube and artificial water-courses of Paris and its The 
lalate the map is the topogrephios! survey by Letellier = Potiquet, 
ts et Chaussées. Its sea 725,000. 
. curves . equal alevaiek are yea at intervals of four ‘aie The 
che. is tinted a ccording to the geo logical formations. On a map of this 
aracter all the drainage by rivers, rivulets, sewers, gutters, etc., is ac- 
surately given. The se of the work is excellent, and its practical 
i ttance is very gre 
Sia Memorie dell’ Obsorsitesis dell Collegio Romano ; Nuova Serie, 
ol. H, dal? anno 1860 al 1863, Pubblicate - = Angelo Secchi, della 
19g. Bulet di Gesu, Direttore, ete. Roma, 1863. 4° (16 numbers), pp. 
Cole This lume contains the siieeinnatiar obsstvacious made at the 
‘is given also a memoir upon the bic ere between meteor- 
Varieties wi those of terrestrial magnetis 
the are given representing the appearance ‘ot the two comets, of 
© Solar eclipse, of the planets Jupiter, Mars and Satu turn, and of about 
Spectra of the planets and fixed stars. 
relations of the second of these comets to the August meteor makes 
- deca ites generales su ae ay pa se ” 
as vies ur les 
fisme terrestre, 12" Vascicule, par V.RAviix. 8¥0, pp. 92. Extrait des 
~~ 9@ la Société Linnéenne de t. xxvi, 1867.—The author 
