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NEW BOOKS A Text-Book of Physiological Chemistry. B! Oiuj Ilun2iizcirsieiz i,~irh t h e (oliuborntioii of S. G . I-lrdiir. S r w v t h Eizgiisir Ediiiorz trcitzslclted j ~ o mfile Eighth Gerirriirr Ediiiorr John . I . Xuriciei. 17 X 2 2 c-in; p p . t,iii I O Z 6 . a Y m J-ork: Joliir TT-iiey a n d S o t i s , 1914. Pric-iz: C‘/cit,‘r Sq.00 net.-The subject is treated under the headings : general and phy-sico-chemical: the proteins; t h e carhohydrates : animal f a t s and phosphatides; the blood; chyle, lymph, transudates and exudates; the h - e r : digestion : tissues of the connective substance : t h e muscle.;. brain antl nerves; organs of generation; the milk; the urine; the skin and its secretions: respiration and oxidation: metabolism. I t used to lie thought t h a t ferments were living organisms and t h a t enzymes were chemical sulictances which could lie separated from the cells and whose acti\-ity was not dependent on the life of the cell, 13. 41. T h e experiments of Buchner have shown t h a t alcoholic fermentation is caused by a special enzyme or mixture of enzymes called zymase. There is now n o a - a y of differentiating sharply b e t w e n organized ferments and enzymes. “ T h e metabolic processes of the living organisms which we recognize as fermentation phenomena m u i t as a rule l i p ascrilied to enzymes acting within the cell.” T h e uames enzyme antl iernirnt arc now generally used in the same sense On 13. 9 5 , the author say5 t h a t when proteids are precipitated 1))- ialt, of the heavy metals, the precipitates (often called metallic albuminates i are not definite conil~ounds h u t are rather to I)c coniidered as loose adsorption compounds of the proteid \\-it11 the same. On 1, 1 0 ~ 3is the statement that ‘ ‘ a sharp line cannot lie drair-ti lietn.ecti the al1iiimiii.i and the globulins from their properties aud this is ihowvn from the researches oi 11011, which show t h a t by the action of dilute alkalies antl warmth upon iliiumin it attains the properties of serglobulin. I t i i evident t h a t we are here dealing with a change of t h e esternal properties of the alliumini t o a greater similarity to those of the globulins, and not with a true transformatioil of the alhL niii, which is free from glycocoll, into g l o h l i t i which contains glycocoll. . Thi is an inqtructi\-c example of t h e subordinate iniportance [ t h a t j the soluhi t y and precipitation properties have in the difiereiitiatioti oi various groups of Iiroteids.” This is confirmetl by the statement, p. 259, t h a t “ a water-solul)le globulin can be transformed into a gloliulin insoluble in water b y careful purification. and also. . . a globulin insoluble in water can sometimes lie converted into one solulile in water b y allowing i t t o lie iii the air. - h i insoluble protein like casein can also, according t o Hammar.iten, ha\-? the solubilities of a globulin due t o the contamination with the constituents of the serum.” The alcoholic fermentation of sugar is accelerated by the addition of disodium phosphatc, 11. 204. and it is claimed by some t h a t a hexose phosphoric acid ester is a n intermediate product. There is still much difference of opinion on this point and it seems to l i e a matter which should l i e taken up Iiy the physical chemist. The question as t o honeycomb structure or sponge structure is a disputed one in the case of the hlood corpuscles, 11, 2 7 2 . “ T h e blood-corpuscles consist principally of two chief constituents. the stroma, which forms the real protoplasm,


anti t h e ititragloliular contents, whose chief constituent is haemoglobin. 11-e cannot state anything positive for the present in regard t o a more detailed arrangement, a n d the views on this subject are somewhat divergent. T h e two iolloiriiig T-ieirs are more or less related t o each other. ;\ccording t o one view the blood-cor puscles consist oi a memlirane which enclpses a haemoglobin solution, while the other X-iew considers the stroma as a protoplasmic structure soaked with haemogloliin. This latter L-iew is in accord with the assumption as t o a n outside l~oundary-layer. T h u s accordlng t o Hamburger the 5tron:a forms a protoplarinic net in whose meshes there exists a red, fluid or semifluid, mass Tvhich consists in great measure of haemoglobin. This nia+ reiiresents t h e Trater-attracting force of t h e blood-corpuscles, a n d liesides this i t is also conv,idered t h a t the outer protoplasmic lioundarl- i. seini-permealile . . T h e researches of Kijppe, Allbrecht,Pascucci, Rywosch, and others indicate the presence of a special envelope or boundary layer, and there is no doubt t h a t the outer layer contains so-called lipoids, such as cholestcrin. Iccithin. and similar liodie.." On 11. $36 the author discusses tlie question w h y the stomach does not tligcst itself during life b u t irithout coming to a n y definite conclusion. 011 11. . i j X he gives d a t a as t o the composition of the teeth and then says: "=\ccording t o Gassinanti. the teeth among themselves have ditrerent cornpoiition, and in man thc wiqdom teeth are poorer in organic substance arid richer in lime than the The great tentiencL- oi the first t o caries i.: proliahly explained canine teeth b y this fact. T h e reason for the degeneration of the teeth is considered liy C . Riise t o lie a lack of earthy salts, and according t o him one find-; the l x s t teeth in localitiey where the drinking water has high Iicrmanent hardness." I i this is correct ~ r apparentl>c h a v e t o choose between hardening of the artcrie, a n d witening of the teeth. 'Thoqe who have read Kipling's ".kt the End of the P ge \rill lie intere,tetl in the paragraph on p. 616 in regard to \isual purple, pigment oi the rods in the retina. ".is the viqual Iiurple is easily destro~-ctll>> light, it tnu,t, thcrefore, also lic regenerated during li[c. Kiihiie h a s also iountl t h a t the retina of the eye ol the frog becomes lileached when exposed for a long time t o .:troiig sunlight and t h a t its color gradually returns when the animal is placcd in the d a r k , This regeneration of the x-isual purple is a iunction oi tlie living, cells in the 1;iycr oi the pigment epithelium of the retina. This may lie iiiierretl irom the fact t h a t a detached piece oi the retina which has been l~leachedliy light m a y h a v e its visual purple restored if it is carefull!- laid o n the choroid having layer.: Oi the pigment-ei)ithelium attached. T h e regeneration ha- incorrodible, b u t were originally covered with a rcally effecti\-e protective coating. Although a definite proof has not been given so far. it seems prolxiblc, from the author's observations, t h a t this protecti7-e coating was simply a coating In of cinder or slag derived from the crude manufacturing process employed an>- case it is cx-ident t h a t . e\-en if the purest pos.;ible iron rcally provci t o lie incorrodible, its use would be limited b y its \oftiless and weakness as compared TT.i/der I ] . B(1iicro.f.t with the better grades of steel." D i ? Chemi- der hydraulischen BindemittEI. BJ IIiliis Kiiiil u i i t i 1i-uiii.r Kndlit~. 17 X 1.) Cm; pp. mi 347. Leiprig: S . Iliusr~l.1915. Price: 14 iiicirk.., hoiiiid.-Through thc work of Kaiikin a t the Geophysical 1,alioratory a n d Oi Kleiu anti Phillips a t the Bureau of Standards, the geueral facts as t o the conqtitution and hydration oC Portland cement are now pretty i w l l estahlishetl. If we workecl with pure lime, silica and alumina, and if equilibrium were rc:iclied. Portland cement would lie a mixture of tricalciurn silicate, 3-dicalcium iilicatc. and tricalcium aluminate. Since equilibrium is not reached, the misturc contairii some free lime arid some dicalcium aluminatc. -411 oi these are cli.tinite compounds with the possible exception of J-dicalcium silicate which apparently can yary slightly in composition 1Iagnesia cau replace up t o ten molecular percents of the lime i n tricalcium aluminate aiid u p t o sir molecular percent5 ol .the lime in tricalciuin aluminate and up to six molecular percents of the linie i n dicalcium silicate. It is probable t h a t magnesia can also replace iome o i thc lime in tricalcium silicate; Iiut the limits, if any, are not known definitely i\.e r, t h a t magnesia may be present up t o 7 . 5 percent ( n o t molcculnr percentages 1 in Portland cement without a n y new p h a w appeariug I r o n i \ probalily present always as tricalcium ferrite, while sulphur occurs a s calcium sulphate or sulpho-aluminate. Tricalcium aluminate sets rapidly to a h>-clratetl tricalcium aluminate m c i dicalciuni aluminate to hydrated tricalcium nluminatc lumiua. Tricalciurn silicate sets to tlicalciuni silicate and lime. while dicalcium silicutc change5 direct to a hydrated ialt. Pure dicalcium iilicate hl-drates extraordinarily ~1o\i-ly,b u t the rate is increased very much by the presence of aluminates, a fact For which we have no esplanation as y e t . I t i-


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nut known what liecomes of t h e magnesia during the setting of Portland cement. Klein a n d Phillip5 sa>-: " T h e hydration oi cements is t h u i lirought a l x u t h y the formation of amorphous h!-drated tricalcium aluminate with or \vith(jut :miorphous alumina, the aluminate later crystallizing. A t t h e same time sulpho.rlui-~iinatecry5tals are formed, antl lov-burned or finely ground lime is hydrated. T h e fimnation of t h e alio\-e compounds liegins within a short time after t h e cement i, :,auged. T h e tiekt compound t o react is tricalcium silicate. I t s h y dration mn>- begin within 24 hours antl it is generally completed Tvithin j days. Betwein 7 a n d r S days the amorphous aluminnte cLinmences t o crl-stallize and 3i-ortho;ilic:itc liegini t o hytlrnte. .ilthough t h e latter is the c h i d constitue n t of the -\nierican Portlantl cements, it i.: the least reactive compound. The early 5treiigth 24 hours 1 of cemcnts is prolial)ly due t o t h e hydration oi iree lime antl the a1utniti;ite.. Tlic increase i n btretigth between 2 4 hours antl 7 (la>-%tlepenti. ul)oii the h>-tlration oi tricalcium silicate, although t h e further li>-tlr:itioii of aluminate.. may contrilmtc somewhat. T h e incr ;antl t1nh-s is due t o the hydration cif d-calcium orthosilicate, encoiiiitCi-ed oppc\iiig forces, in t h e hyrlration cf any high-l)urnccl free lime p i - c ~ . e n t .inti in the cry.;tallization oi the aluminate. I t is t o this hydraticm t h a t is d u e the lolling oii' in strength lx.twcen 7 ant1 r S days oi \-cry high-liurnctl, highlimed e c n i e n t ~ .whereas the tlecreiiae 4ion 11 ljy e high alumina cements i i d u e ti) the cry~talli7ationd' the aliiminate. Fina i n the cement i i reilline hydration 1Jrw -i\tive t o h:-dration a n t i doe; n!it iorrn miy (1 i!iicts. liut oceui-s :I\ :I i-iist-like material ~


'The I)i)ok lib- Kuhl aiicl Knothe i\-:ii rrritten too iooi1 t o include the work oi Kleiii and P h i l l i p or the filial paper ljy R:iiikiii: liut it gives a very 3atiifactory . ~ c c o u n tof niir knon-letige u i ) t o the Iiegiiiniiig oi 1914. T h e author5 g i w \-arious iticationh oi cciiieiit- ~ n then d tliscusi t h e wrioub raw materials. T h o n i, tlc\-otetl tii tiiiiinterid hydraulic r e m e n t i . I.ritler this head c( ilraulic lime.\ ;ind Roinan ccincnts, t h i i latter liein:. the European term lor what \ r e ecill Ro-ciirlale cement or natural ccinenti. The third antl iourth v c t i o n s deal 17 ith the theor>- :uid practice oi iintcretl hyclraulic cementy, meaning Portl a n d eemciit thci-eiiy. T h e tifth 5cctioii i i devoted t o cetncnts inadc o u t of lateiit 1iytlr:iulic ,ulistniit meaning thcrcliy Iiozzolan cements, cement.: from etc T h e authors a>-, p .?o;, t h a t "making piire Portland t furnace