NEW BOOKS Das Princip der Erhaltung der Energie, und seine Anwendung in der Naturlehre. By I ~ ~ i 1 s J l 2 ? r z i s c h f i r16 . x Z J ciit ; p p . .I* riiid djj. Z~(~ipzig: L?. (,'. Price ; c,'oth / z Triui-ks.-There can he h i t little rlouht that tlie T e i i h ? r t ~1Sy7. , actaal results of our study of physical science consist essentially i n a more or less exact knoxledge of the relations that measurable quantities hear to one another. -1treatise designed to present the facts of pliJ-sical science in general should. therefore, lie concerned Tvitli these relations thetnselves. together \\-it11 the \rorkitig niethod or i n e thods by means of which they ha\-e been discor-ered. Of such nietliods t h e most significant at present is, unquestional)ly, the energy theory. T h e procedure of t h e energy theory cotisists. as el-eryotie k n o ~ v sfirst , i n seeking the \~-ork-equir;ileiitsof physical trianifestations. aiid then in assert.. i n g the constancy of the :ilgetxaic sum of all amounts of wdrk and of workequivalents that undergo change in an>-process considerell. This assertion of conservation rests, of cou-se, upon the principle of the excluded perpetual rioti ion, which \r-e recogiii;:e in its turn as nothing other tlian a siiuple expression of t h e ultimate scientific postulate t h a t definite relations do subsist airiong t h e measurable parameters \\-hoseclianpes tleterniine physical pheuoniena. .1further elernei~tof t h e energ!: theory is, to he sure. t h e determination of the potential. and therefore of the corresponding quantit!--coorcliiiate. of any gix-en workequivalent,--i, c . , in hrief, the 'potential theory'. .1ccortliiig tu this. an ideal erposition of t h e outlines of physical science must either s h o ~ i~n . historical order, how the energy principle. whether consciously or ~ i i i c o ~ i ~ c iapplied. o~i~l~ has reached its several results : or i t must first describe and justify the tiiethotl itself, a n d thereupon c1eta.J in some logical order the actual applicatioiis of it t h a t have beeii made. Januschke. in his Pt'iti,rip der- E~haZfir7ifidel E ) i e f : ~ i ehas , followed tlie latter, or more deductive. plan ; and i t may l ~ said e that lie has made a brave aiid praiseivorthy attempt to give a connected account of the real facts of physical theory. I11 his o ~ \ - nxords : Im vorliegetideu Buche sollei! Geltimg uiid .-\nwenduIig des Energie-priucipes i n alleti Gebieteii d e r S a t u r l e h r e dargethati werden. E s g e h t a u s rieljiihrigeii Studien iiber die verwendung des genannte-1 Principes fiir deu hiiheren Uiiterricht hervor [ h e is Director of t h e Ohtw'enlsi.hi~le i n Tesclien]. n l i n l i c h B U S den1 Bestreben. mit Hilfe d e s P r i n c i p e i nnch einem einheitlichen P l a n e sowohl die einzeltieii E r s c h e i u u n g e n eindringlicher L I I I)ehniide!ii. a i s a u c h d e n Zusarnmenhang derselhen tnijglichst innig E L I gestalten." ' I
In the working out of this plan the a~itliorh i s etili\-eiied his text by the addition of considerable interesting and well stated historical itiforination : :mdh e has simplified things by u+ing the calculus iiotatioii freely, altllough without introducing a n y extended anal>-tical de\-eloptnents. Of the 450 pages of the
hook, 104 are devoted t o t h e dyiianiics of solids ; 20 pp each to the dynamics and statics of liquids aiid of gases respecti\-ely : 69 p p to what are uiifortuiiately termed ' niolecular forces', -namely cohesioii, elasticity. capillarity, and osmotic pressure : 6; p p to heat : 133 to electricity and niagiietisni ; a n d 2 2 to light. .llthough the book is not a treatise on p h y i c a l clieiriistry proper i t is interesting throughout to the physical chemist. antl this is particularly true of t h e estendecl chapters 011 t h e 'niolecular forces', on heat, atid on electric currents (really electroclieinistry i . Oiie-compoiient systems are treated i n sorne detail iii t h e chapter on heat : polycoiiiponent systems. on tlie other hand. are not given aiiythiiig like due comitleration. The tlisappoiiitiiig feature of t h e work is tlie author's weak grasp of t h e three great ideas upon which the eiier,gy theor>-is liuilt : the idea of t h e relativity of physical plietio~neiia: that of the potential. and of tlie correspoiiciiiig quantity-coordinate. of each work-equiralent : aiid the conceptioii that ' bodies' are complexes of sense-elerneiits. K e p r d i i i g the first of these points, the author's vagne idea that ' ' The prohleni of natural science is to gain a n uinclerstaneling of natural plieiionienn" ( ~ 2 .9' contrasts unfavoralily with. for instance, I I a c h ' s ' The aim of all [physical] research is to ascertain tlie riiode of connection of t h e sense-elemelits that constitute iiotlies' , I , p ~' ,\vlierel)!-, of course. it is uiitlerstood that these modes of connection are to be espressetl in terms of the physical paraiiieters that are tleteriiiinetl by -are iuinctions of - tlie seiise-eleiiieiite. If the author hat1 heen clear on tlie secoiitl point lie could not liave classified forces. tensions. and pressures. iritli theriiioilyiiarIlic temperatures. electric potentials, etc., as 'iiitensity factors' ; for these are not tlie sanie kind of thing at all. -the former are forces. tlie latter are true potentials. He coulll not have fallen into this tlifica1t)- iiad he perceived tlie fiuiclanieiital tlistinctioti - the one lieiug t h e protluct of a force into between work and ~1.ork-equiv~~lents. a change of space, the other the protluct of a potential into tlie change of a quatitity-coorcliiiate. =\tit1his antiquated nietaphysics. fillally. ( t h e third pLiiiit; is eseiriplifietl liy the naive aiicl helpless reiiiark that The p i ~ i ~ ~ 7 n selisec~/t,~ affecting part of t h e things aliout us \\-e tertii . . . iirtrtfri-or szhstczirre : spatially liniitecl inatter is called body" ( p . 2 ' . Is this irresponsilile rnetaphysical ghost ' matter' n e w r to tie liaiiishe(1 from anion:: 11s? . l i i t l \vliy slioultl physicists. of all people. lie the ones to cling so tenaciously to a crude aiitl outworn inaterialism ? Physics, antl cheniistry with it, ha\-e to (lo with lmtlies. - they do not h a v e to rlo Tvitli ' iiiatter'. \ l y e inay say of our author. ho\\-e\-er,ant1 w e say i t gratefully, that he '. makes 110 u s e of O;tx\\-altl's L-iew that energ>-is a real agent. ' ' Sotwithstaiitlitig the \\-eaknesi of the author's funclarneiital scientific ideas. the general plan of his book is fairly gooel. aii(1 tlie tletnils are, on the whole. clearly aiid sensihly put. -1s a work for geiieral reference, sntl as a presentation of x h a t might almost lie calletl the pli>-sicsof physical chemistry, it caniiot J . E . Trez'oi, but prove a useful hook. I '
Die Energetik, nach ihrer geschichtlichen Entwickelung.
~ ' J I
(leo7.g
HE~III.
15 x 23 ciii ; $# .rii 17ild 370. L e i p z i r : 17ecil r c i i t i Colufl., 18yS. 1 3 i c c : pnfiei, S.60~ii~7rk.s,-Iii the course of the \-igorous riiscussioii of the riel\- 'eirer1 The it,ilics a r e t h e a u t h o r ' i .
A 1 7 ~B~O t ~O ~ S
38;
getics'. carried on in Germany in Isgj-96, chiefly hj- Helm, Roltzmann. and Ostn-ald. Helm announced that he hac1 in preparation a conipreliensive work 011 t h e historical developnietit of the energy theory. This l011g ;i\raitetl hook is 1 1 0 out. ~ and its appearance n-ill unquestioiiahly he g e e t e ( 1 \\-it11 a n-itle-spreatl interest. To allow t h e auzhor hiniself to speak first for it, we Iirint his preface entire, reserving for our next issue a detailed esaininatioii of the bocly of the. test. T h e quieting ii: " Although produced in t h e midst of strife. t h i s book is not a poleiuic. fluence of t h e y e a r s t h a t h a v e passed sirice t h e excitement of t h e Lliheck days briugs w a r r a u t t h a t its p a g e s will t r e a t quietly of t h e acquisition a u d outgroxviug of opinions, a n d of t h e s t r u g g l e f o r t r u t h a u d for recognitiou of e r r o r . 111 a few p l a c e s , pnrticu1,irly in P a r t TI.i t will b e Iioted. - iiidulgeatly I hope,- f r o m t h e h a l t i n g of t h e book t h a t it conies f r o m battle. In t h e s e p l a c e s a p p e a r discussiolis t h a t correspoiid i n extent neither tc t h e difficulty of t h e que.5tions considel-ed, iior to their infliietice. S o t as iu t h e retnaiuder of t h e !look could t h e allotment of s p a c e h e r e be ~ o v e r i i e c l solely b y at1 estimate of t h e value a n d import of t h e iiir-estigations presented ; t h e xrriting h a d to h e done with a view to d e f e n s e . ' ' O n e guiding idea. however. is n n p r e m e t h r o u g h o u t t h e b o o k , E n e r g e t i c s , a s it hac del-eloped from t h e d a y s of Robert Mayer to o u r own. is i n its honlo-rneity of cha:acter a uuiqiie kiiid of comprehensive knowledge of uature. E r r o r s and excrescences h a w iiideed a p p e a r e d a t a l l s t a g e s of its development. a s is also t r a e of m u c h t h a t f i i ~ d sg e n e r a l a c c e p t a n c e to-day. But h e w h o h a s a 1 1 appreciation 01 historical d e r e l o p m e n t understaiids that useful g r o w t h s a n d t h o > e t h a t require to b e p r u u e d a w a y a r e a l i k e prodiiced b y t h e saiiie fo:-ces. T!:e b o o k I-eyisters protest, t h e r e f o r e , ag:iitist r e g a r d i n g e i t h e r single i ) r n i ~ ~ hUrIi teinporary iniscouceptions a i coustituting t h e t r u e eiiergetici - a i its opponents have sou:- .Inti whether one considers the great practical services rendered to organic chemistry by the theories of constitution, or their almost total want of coiinecrion Tt-ith tlie recent work iii general chemistry. it can hardly he denied that the subject is much better discussed in a volume to itself than - as is the case in oiie well-known work - iii a chapter \vedged hetween ’ tlie theory of solutions ’ and ‘ the action of mass ‘. The book begins with the laws of definite and niultirile proportion. ’’ the fundamental laws of chemistry ”, leading to the coiiception of atonis : next come the investigations of Ga>--I,ussac, and the niolecular theory, a short chapter ( j pages) on the deteriiiinatioii of molecularweiglits: iii solution, then atomic heat. isoniorphisiii, and filially the periodic law. \vhat is logically the secoiirl division of the work is iiitroducetl by a long chapter on valency, in \\-hich the evolution of that coiiception is traced to its present state : a definition of the ‘ constitution or structure of cliernical cotnpounds ’ folloivs. and the rerriaiiiing two hundred pages 1 except thirteen on chemical affinity) are devcted to full discussions of the constitution of various classes of compounds, organic ancl inorganic. and to the connection between 1V. Ltrsh ,lZillev chemical constitution and properties of compounds.
A Treatise on Magnetism and Electricity. By A?tdvcw GI-ny. Iiz t x f o ivi1701. I. 1’6 X 23 c i i i ; pfl. nitd 479. A\7ew Yo)%: The lJlac~)ii/lcrr~ Co.. 1S97. Price : $4.50. --The subjects of the chapters are : permanent magiietisni ; magnetic ititeiisi1.y and niagnetic induction ; terrestrial tnagiietisrri : tnagnetisni of an iron ship and conipensation of the compass ; elementary phenomena and theory of electrostatics ; steady flow of electricity in linear coiicluctors : general dynaniic:tl theory : motion of a fluid ; elementary facts and theory of electromagnetisrri ; induction of currents ; dytianiical theory of c u r rent induction : general electrotnagtietic theory ; the voltaic cell : thertiioelecIIIILES,
tricity. .it first sight it ~vouldseem as if this book coiitainecl little that woulrl interest the chemist : but i t closer inspection shows the incorrectness of such a view. The chapters on tlie elementary phenomena and theory of electrostatics, on the elementary facts :ind theory of electroniagnetisni. and on iiitluction of currents contain many things that the chemist sliould kiiow ; while the chapters on the steady flo\\. of electricity in linear conductors, 0x1 thermoeiectricity, and on the voltaic cell, contain niatter that is quite as important to the chemist as to the physicist. The chapter 011 the voltaic cell is oiie of the poorest in the hook : but the reason for this appears to he that tlie more interesting phenomena are to he treated in the second volume. The general style of the hook is so good that one is grieved to read, even in a quotation, ahout “ the energy expatided in algebraically geiierating reversible heat.” The typograpliical errors are few in number and consist chiefly of dropped letters. 1ViIdev D . Bancvoff Practical Exercises in Electrochemistry. B,v F.Oetfel. Audhorized tvn?2sIntiotz by E&nr 1”. Shzith..1’3 X 17 c m ; flp. z’ii a?td 92. Philnde/phin : P.
BlnFisfotr.Soil
Co., r-iiigl q o n d the scope of tlie book, but the omission is conipensated in some measure by appended iiotes on Massieu's characteristic functions. on the continuity of liquids a n t i vapors. etc. The result. as a whole, is a simple and fairly well rounded treatriient of general thermodynainics. J . E . T".eivw
Zssxed 21ndei. Science Abstracts : Phj~sic.s nird E l e r f ~ - i e nEiig?iiewiirCy. l f h e dii.fcfioir o f the ItisfifritioiL of Elecii,iral Eiifiiirecn mid f h c Phj'sictr2 .Yocicfj, of / ~ o ~ r d o i i . l'oI2riire I, c r ~ i ~ e i rnziilt6ei.s; t 16 x a,! cl~z. L o i ~ d o i : t s/r ilZiiigs. posl Tilj ,201- t i it ii Fiz it cis, 1S5S. Pvice, f o ii ai i - iiie iir 6er.s f / i irfj~-.six free. pci- nuitriiii. - n-e are glatl to call attention to this new enterprise. I t
-1i.n) Bonks
39'
appears to be a developiiieiit of tlie series of reviews that was formerly published by tlie Physical Society of Lontloii iii its Transactions. I t is issuetl monthly under t h e tlirectioii of J . Swiiihurtie. wit11 collalioratioii of IV. R. Cooper as sub-editor aiicl u:icler the general super\-ision of a coiniiiittee appointed froiii tlie I'hysical Society ;inti t h e Institute of Electrical I?iigineers. T h e list of a h t r a c t o r s cotriprises ahout fort!- ~ve11-k11o~v11 iianies. anti this staff is being enlarged. Tlie 1iuinl)ers for January. February, March, and .1pril contain 470 ahstracts, and \ve are assured that the monthly parts will be considerably erpaiitletl as time goes 011. I~liysic(,clieiiiicalitems appear. of course. under most of the heatls uiicler which t h e reviews are claqsified, and tlie . make up pretty niuch all of the sections on ' Heat ' aiitl ' Electrocheinistr- and Chemical Physics. ' -1s an intlex and critical digest of current work in physics. this at1tiiiral)l~-coilducte:l journal deseri-es cordial support from Ehglisli-speaking men of science. /. E . T Y ? Z O V Die Fortschritte der Physik iiir Jtrizre 1896. t/tri:gesfrlif i'oic ~ E phj,.riktr/Y ischc,ii (;csEl/.c(.Irnfizel Cerliii. 5 r r i j ~ ~ In. Pur-t r 11~. l'hj'sics oJfhc EfIici. ;mdi?td h y R i r h t i d Edi.iisfeiii. rti x 2.7 ciiz ; fl$. .y/i.x tried ~ r , ~ c i r / . r r j i ~ ~ ,f-'. ei~~r: I 7itm~e,rr CYS ~ h i r r'q57. , Price : f l ~ r p r i ~ j) oi ~ t ~ r k,~ Tlie . thoroughness antl the conipreliensi\-e scope of t h e Forfsr/ir*iffe d e l , Physik coiitiiiiie to he e\-idelit iii t h e present Part 11. for the year rS96. This large section is20 large octavo pages) of the year's output reports progress iii light, heat, :inti electricity, the greater part of wliicli is xvork of a physicocliemical nature. r n d e r the heatling 'Jiglit' is suniiriarized t h e work of tlie r e a r i n refraction, c1ispersio:i. sliectra. luniiiiescence. rotation, anti photochemical action ; under 'I-Ieat' are consitieretl tlie energy a n d the entropy la\rs, tlie kinetic theory, expansion. tlierinocheniical (lata. fusion. vaporization and ca1orinietr)- : under 'Electricity' are assemhletl the verj- exteiisive researches in electrochemistry. hesides the work in electricit!. aiitl niagiietisin that has a niore purely physical aspect. Tlie \-alue of these compact reviews of nli t h e XI-ork doiie year 1,- >-ear in our special sulljects anti iii those iinniecliatelj- related to them is hardly to be overestimated. 1.E . Tt~c~vo)Monographieen aus der Geschichte der Chemie. E d i t e d hy ( ; € O r $ . IC'. A . Ahh/hnriirs. 2, He/? ; Die Einfiihrung der Lavoisier'schen Theorie, im Besonderen in Deutschland ; Ueber den Anteil Lavoisier's an der Feststellung der das Wasser zusammensetzende Gase ; /JJ, Geor;
