P t 26.76. VI.-Ow M L Alknloi’d from Chtchona Bark hitherto Undescribed. results :- 7 Pt. ‘r 26.63 26.62 Gerhardt’s formula for the anhydrous platino-chloride of quinine C,,,H,N,O2 2HC1 PtCll requires H 3.53 The salt taken for analysis was precipitated from a hot acid solution and was a distinctly crystalline powder. The composition is the same whether it be precipitated cold in a By DAVID HOWARD. IN experimenting upon impure crystallisations of quinine salts obtained from the mother-liquors of the manufacture of sulphate of quinine I have occasionally been perplexed by an unusual loss in recrystallising which the mechanically adhering mother-liquor did not seem to account for. A more careful examination of some of these substances shows that the cause in some cases at least is the presence of an alkaloid hitherto undescribed the extreme solubility of the salts of which both dis- tinguishes it at once from the cinchona alkaloids already known and renders it very difficult to separate from the uncq-stallisable quino’idine.The most convenient method of obtaining it is to purify the alkaloids contained in the mother-liquor from the recrystallisation of such impure products as I have mentioned by solution in ether and after evapora- tion of the ether to dissolre with oxalic acid in as small a quantity of water as possible and allow it to crystallise. The oxalate thus obtained may be purified by recrystallisation from water with addition of animal charcoal but I have never been able to free it entirely from a yellow colour.The most satisfactory salt for analysis is the platino-chloride which is prepared in the usual manner ; it is almost insoluble in water or in cold hydrochloric acid but soluble with difficulty in hot strong acid; it forms a crystalline powder by precipitation ancl well defined crystals by solution in acid. The analysis shows that it is isomeric with the platino-chloride of quinine but anhydrous instead of containing one atom of water of crystallisation given off a t 120” as does the salt of quinine. The ultimate analysis for which as well as for the other combustions which I shall have to mention I am indebted to the skill of Mr. Huxley and Mr. Gray of the Royal College of Chemistry gives the following Experiment I .. . . . 32.67 H. 3.67 3.82 C. I1 32.67 C 32.60 G VOL. XSIV. neutral solution or crystallised from a strong acid solution as the fol- lowing results will show :- do Platino-chloride precipitated cold Pt 26.50 crystallised 26.68 ' The oxalate as I have before mentioned though it is the most easily ci-ystnllised of the salts of this alkaloid is unfortunately very difficult to purify entirely and changes so readily under the influence of air light or heat that I hare been unable to obtain it colourless. When a dilute aqueous solution is concentrated by evaporation in a mater-bath tlie change of colour sliows that decomposition has to a certain extent taken place and on the addition of water a brown resinoid matter sep:wates from tlie solution.To find out if this was caused by im- puriries or was a property of the salt itself I decomposed the platino- cliloride of known purity by several processes but iu each case the resulting oxalate had the same colonr and the same tendency to decom- pose. Even when prepared from perfectly colourless solutions of the dlrnloicl in ether I hare still found the oxalate of a greenish-yellow hue even before the application of heat ; in fact I am not sure that this colour may not be inherent in tlie salt itself. I t is exttemrly soluble in water tlie wet crystals melting a t loo" but inucli less so in cold water ; insoluble in ether but very soluble in alcoliol ancl to a less degree in amylic alcohol from hot concentrated solutions in either of which menstrua it crystallises freely on cooling.The water of crystallisation is partially given off in vacuo and entirely a t 100" after previous drying; if the salt is at once heated to 100" witliout prcvious exsiccation it is apt to fuse. The conibnstion proved exceedingly difficult ; the usiial process with cupric oxide was found inadmissible the oxalate assuming a dark brown colour as soon as it touchcd the oxide. The only practicable method is buriiiag in oxygen gas ancl even in this mode of analysis the low temperature at wliich tlie substance partially decomposes makes it diflioult to accomplish successfully. It will be seen that the results though agrceing very closely among themselves differ considerably from tlie probable formula showing plainly the difficulty of obtaining a purc product.The hydration and the oxalic acid point to the formula 2(C,,H,,N,O,),C,H,O + Saq. thc numbers obtained being :- H. 7.55 8.64 8 . i 4 C . Theory . . 56.00 Exp. I . 57'57 , 11 57.42 , 111. 57.74 , IV . 5i.85 9.14 8.79 CSHLOI. HLO at 100. 1 1 2 0 in vacuo. 14.23 14.09 10.00 10.07 9.98 10.08 18'00 17.98 17.98 17.89 l i . 7 2 14.02 13.82 10.23 10.19 17.98 - - 7 ) v * - - HITHERTO UNDESCRIBED. G3 The water lost by drying in racuo agrees very closely with 7 atoms viz. 14.00 per cent. ‘Ihe salt thus differs from oxalate of quinine by 3 atoms of watcr of crystallisation the foi-mula of the latter being 2( C,oH,,N,Oz),CzH,O~ + 6aq.The properties of the other salt,swhich I have examincd arc as follows :-The sulphate tartrate citrate hydrochlorate phosphate and acetate are all exceedingly soluble in water ; on evaporation in vacuo they form semi-crystalline masses impossible t o obtain in a state fit for analysis. The hydrobromate and ferrocpnide obtained by double decomposi- tion form oily strata a t the bottom of the solution solnblc in an additional quantity of water but eren on long stancling thcy show no sign of crystallisation. The hydriodate also forms an oily stratum in strong solutions but on standing it becomes semi-solid by the formation of crystals ; n-eaker solutions also deposit a small quantity of flocculent crystals but in neither case can they be separated from the mother-liquor.The sulphocynuide while also forming an oil when in concentrated solutions crystallises from a somewhat larger quantity of water in long silky needles almost white rery soluble and readily decomposcd by hcat. The iodo-sulphate I have not as yet succeeded in forming. I much regret this on account of the great importance of this salt in the cin- chona alkaloids and further experiments are needed either to form it or t o prove its absence. The alkaloid itself as obtained by precipitation from a solution of its salts by potash o r soda is a yellowish oil. I have not bcen able to obtain it pure in the solid state for it mill not bear heat without decorn- position and holds water too strongly to dry in vacuo. It is very soluble in alcohol soluble to a large extent in ether from which it separates as an oil when the ether is allowed to evaporate.It is B strong base ; the salts are neutral to test-paper ; a small exccss of the base strongly restores the colour of reddened litmus. Ammonia pre- cipitates its solutions but imperfectly and if we may judge from this it is even a stronger base than quinine. Chlorine-~vater follond by ammonia produces in solutions of its salts the green colour and precipitate of dalleiochin which distinguishes quinine and quinidine. Strong acids even in the cold produce a change of colour and even Tvhen dilutcd with a considerable quantity of water ; heat renders the action much more rapid. This coloration is strongest when nitric acid is used an excess of which with the aid of heat will develope a strong yellow-green colour even in a meak solution.In this reaction as well as in the persistent colour of its salts this alkalo’id shows a curious resemblance to aricine. G 2 EKIN ON THE ORIGIN OF NITRATES i ' 1 VII.-Ou the O,?giiz of Ai'trates in Potable TVizfers. By CIIARLES EPIS Batli. 64 The yellow colour renders the examination of its optical properties difficult but as far as has been hitherto tried it is inactive. I hare not been able to recognize fluorescence in its solutions. Its taste is a pcculiar bitter very much less both in intensity and permanence tlinii that of the other cinchona alkaloids. I have not been able to find out whether this alkaloid is contained in all the species of cinchona or if not to which it belongs for the diffi- culty of tlie crystallisation of the impure salts makes it a matter of uncertainty to obtain it.My unclc Mi-. J. E. Howard when investigating the leaves of the Ciiicliom Siccci~nLhmc from India found minute quantities of an alka- loid soluble in ether froni which an alcoholic solution of oxalic acid precipitated i t in a crj-stalline form ; bat the small quantities a t liis disposal prerented his examining it further than to show its analogy 7Vith quinine ; his present conviction is that this substance is identical with the alkaloid I hare been describing and though the eviclencc is not yet sufficient to cnable us to speak with certainty it teiids strongly to prove it. It seemed so desirable t o settle this point and to tlirom some light if possible on the order of formation and possibly on the fnr more important and far more difficult question of the mode of forniation of the alkaloids of the descending sap that he has written to Mr.Broughton and we hope shortly to receive a quantity of the leaves sufficient to enable us to investigate it. I DAVE frequently been a t a loss to account for the presence of con- sidcrable quantities of nitric acid in potable waters where contamina- tion by sewage or manured land was out of the question. To give but ono instance tlicre is a hill near Bath capped by the Great Oolite which has not a siiigle house upon it no drainage near it and on n-hose scanty herbage browse oiily a few sheep and yet the springs rising a t tlie junction of tlie Oolite with the Fuller's earth contain as much as . r j j grains of nitric acid per gallon. Here then after making all due allom- ance for the combinecl nitrogen contained in rain water which according to tlie observations of Lawes Gilbcrt and Way amounts to .?+k parts nitrogen in l,OOO,OUO tliere still remains the large proportion of eight to one to be accounted for. And this proportion will be still further increased if we consider that much of the nitric acid and ammonia