i88 



SCIENCE. 



CHEMICAL NOTES. 



The Optical Properties ok Mixtures of Isomorphois 

 Salts. — H. Dufet has verified the law which he communi- 

 cated to the Academy, April S, 1S7S, i. <•., that a crystal 

 formed of a mixture of two isomorphous salts has indices 

 of refraction, which van- continuously with its composi- 

 tion, so that the variation in the value of the index is 

 proportional to the number of equivalents of one of the salts 

 introduced into the mixture. 



Influence <>f Temperature on the DISTRIBUTION of 

 in their Sou riONS,— In all salts the concentration 

 of the heated portion decreases and that of the cold part 

 increases. The difference thus established increases with 

 the original concentration. In the series of the alkaline 

 chlorides the differerence is so much the greater for the 

 same absolute concentration as the molecular weight is 

 higher. The phenomenon seems to have no relation with 

 the curve of solubilitv. I 



Rise of the/ . in Mercurial Therm OHXTERS. 



— The zero-point rises further and more quicklv in ther- 

 mometers of '• crystal " glass than in those lree from lead. 

 The rise of the zero-point is much more rapid at the outset, 

 and tends probably towards a limit for a very prolonged 

 heating at a fixed temperature. The effect of an elevated 

 ram re renders the thermometer more stable under 

 the inlluence of heat at any lower temperature. 



|. M. Cbai is. 



Devei opMENi isv Pressure of Polar ELECTRICITY in 

 1 1 em hi eur \i. Crystals with Inclined Sorfai ks. — What- 



ever may be the detei mining cause, whenever a hemihedral 

 non-conducting crystal with inclined surfaces occur-, there is 

 a formation ol electric poles in a certain direction; whenever 

 tin- crystal expands the dU ::ieity takes 



place in an opposite direction. 



MM. I.v ques and l'n rre Curie. 

 now 01 l'i km am. \x a 1 1 i pon l'"i issn m Cyanide, — 



This reaciion pioduces much nitrite and a little urea in 

 an alkaline medium, whilst, il the liquid is acidified with 

 sulphuric acid, urea is formed in abundance. The simul- 

 taneous formation ol two incompatible compounds, urea 

 and nitrous acid, under the influence of pi imanganate, 



•howl thai the nitrogen of the cyanogen is exposed at once 

 to an oxidising action and to bydrogenisation. 



I . Baudrmon 1 . 



;ivk Solubility 01 Lead Phosphati and 



riATE in Dilute AcETi 1 >ne pan ol bad 



■ n- ol dilute acetic ai id al 



;.an ol bad phosphate requires only 



I pails Ol the - • IND Bl I 1 K \nd. 



> \ 1 \nim \i I i 



l ; - dui to ■ decomposi- 



I the fluids in tin 1 led immediate Ij aftei 



\i in-t volatile 



fattj rived from the incipient d< 1 om- 



• the albui lily followed by tin two 



I 11 rh bi 1 a tissue 

 On- bi id reai tion prevails 



1, tin mil'" l< IS and the lungs. 



• in the i In the latei 



11 and an 



in lati 1 an alkaline 



■ I, nun h .mini a bl - 



I 

 1 11 >>l 



inaiiii- 

 llll 



ills l.( 



.1 III . 

 \ I 



I i (J 1 1 



' till I. 



SOLUBILITY of Recently Preciittateu Carbonate of 

 Lime in Ammoni ■.« \i S \i re in Presi NCE OF AN EQUIVALENT 



Proportion of Sodium Chloride. — At the temperature of 

 10 to dissolve 1 grin, calcium carbonate there are required : 



Ammonium hydrochlorate 13 9S0 grms. 



" sulphate S.3S0 " 



" nitrate M-43S '* 



Armanu Bertrand. 



Purification and Refining of Fatty Matters.— 



To determine whether an oil is pure, M. 0< r \\ 1 ALLAIRE 

 takes a piece of carbonate of soda (crystal), the size of a 

 nut, dissolves it in iis own bulk of water, and shakes it up 

 with the oil under examination in a bottle. If the oil be- 

 comes turbid, and gives, on settling, a solid bulky deposit, 

 it has been badly purified. Oils which act upon the metal 

 of lamps and form deposits ol verdigris are also to be re- 

 jected as impure. Commercial samples often contain 10 to 

 15 per cent, of free oleic acid. 



Remarks on i he Pi \ riNUM Sui PHOCYAKIDX OF V. M \r- 

 . — This body is not a platinum sulphocyanide, but a 

 potassium platino-sulphocyanide, having in its anhydrous 

 state been long ago analysed by M. Huckton. Nor docs it 

 yield a proof of the OCtO- atomicity of platinum, which in 

 this case, as in many others, is teti.uomic. 



G. Wyrouboff. 

 a Compound of Titand mTetx ichloridb ind Acetyls 



CHLORIDE — On mixing these two bodies the compound in 



question is immediately precipitated in small yellow bril- 

 liant spangles resembling lead iodide On exposure to 

 moisture thesi crystals undergo a change, liberating hydro 

 chloric acid. They mav be preserved in dry air, 01 pre- 

 ferably in dry hydrochloric acid. They melt at 25 to 30 

 and crystallise OO cooling. In contact with alkaline solu- 

 : hey are di 1 . forming an alkaline acetate and 



chloride, titanic acid which is precipitated, and water. The 



analysis of the crystals yielded results agreeing with the 

 formula c.lloci+TiCL. Armand Hi strand, 



Cei •■ 1 kiiis oi M ixtures of Methyi Cyanide: 



wiiii Common Alcohol and Mbthvlic Alcohol, — In 



order to sepsrate methyl cyanide from alcohol it is d 



s.u\ to submit the niixtiue to fractional distillation in older 



to classify the products ; then to dissolve the largest 

 ble quantity ol calcium chloride in the mixture, boiling at 

 the lowesl temperature in ordei to absorb tbe alcohol ; then 

 to distil sgain in the water-bath, and to submit again the 

 product thus obtained 10 fractional distillation. A verj 1 ii h 

 cyanide la tims obtained, from which the Last trai 

 alcohol are eliminated by distillation ovei ■ small quantity 

 oi phosphoric anhydride, and by rectification to remove the 



small quantity ol ethyl oxide and acetate which nise 1 10111 



the reaction <>t the phosphorii ai id. 



C. \'in. 1 n 1 and B. I'm U manai . 



Determination 01 Urea b\ Sodium Hypobi 

 1 Mini criticises the memoirs >>i M Pauconniei and 

 M. [ay {Bulletin 4* la Sec. CJumiatie, sxxiii., pp, tos and 

 In opposition i" tin loimei ol these chemists he 

 finds that the presence ol 1 me-sugai distinctly augments 

 the quantity <>i nitrogen evolved from una bj means oi 

 sodium bypobromits. In opposition 10 M |a) he 1 onsiders 



thai it is ( .is\ in meet With Starch lyTUpS, which e.i\c ofl 



merelj an losignifii ant quantity "I ammonia if heated with 



1 SUStll ■ 'da. 



1 lii mi the III in nl S< In 1111 1 • l\"tt. Opened at 

 the l.i "I I Ai .nli inn ,les S, k ii. ■ s, n I, ,s | , an 



improvemenl in allsarin steam ml\ bj piloting upon 



previous!) prepared with emulsive ml, mixed In 



certain th hypochlorite <ii soda. F01 producing 



cadmium sulphide directly upon thi fil M chmld 



1 mixture "i arsenioua si Id, sulphur, sodium si etate, 



1 dm 1 u in mi i.ite. ^ inn yellow is obtained i'\ steam 



: 1 to S hours and an orange Is produced b) Increasing 



dllllll .11 1 I 



\ j..i| 1 r bj M. Zii opened, re* ommendii 



addition " ! u Id to tin 1 • l< >m i.e. u la 



on! 10SCS. 



