2 68 XXIV.-On the Composition of Japanese Bird-lime. By EDWARD DIVERS M.D. F.R.S. and MICRITADA KAWAKITA M.E., F.C.S. of the Imperial University T6ky6 Japan. NO results worthy of publication seem to have been obtained in the examination of bird-lime uutil the year 1884 when J. Personne (Compt. rend. 98 1585) made known those obtained by his father and himself. When that paper appeared we ourselves had been for some time occupied with the investigation of Japanese bird-lime and had already obtained results which proved to be in general agreement with those of Personne and yet sufficiently unlike them, and in some respects in advance of them to lead us to continue our work although he had promisedfurther attention to the subject. Up to the present date however nothing more from him has appeared, and we now offer this paper as an extension and partial confirmation of his observations.Bird-lime or tori-mochi is prepared in Japan just as it is in Northern Europe from a species of holly by macerating and pound-ing its inner bark in water and afterwards picking out the fragments of crushed tissue from the viscid mass. Bird-lime exists ready formed in the bark in great abundance and is not apparently modi-fied in any way by fermentative action during its preparation. I n Europe it is prepared from the common or prickly-leaved holly ( I l e a aplLifoliU7?2) but in Japan it is obtained from Mochi-no-ki the I. integra of Thunberg (Prinu,s imtegra H and A.). We are not familiar with bird-lime as prepared in Europe but judging from descriptions Japanese bird-lime is like it except perhaps in not having a greenish hue although of that even we are not certain since the Japanese product may well have it sometimes when quite freshly prepared.Bird-lime is extensively used in Japan as in Europe for catching birds and insects and with the usually attendant cruelty. In manuals of economic botany we find enumerated as peculiar constituents of the holly a bitter principle named ilicine an aromatic resin and bird-lime itself. I n the account of bird-lime given in Ure’s Dictional-y the true substance is not well distinguished from the viscid matter of mistletoe (Viscurn aZbum) examined by Rejnsch from which it appears to be entirely different. Some ProFerties of Japanese Bird-lime. The bird-lime is pde-greyish nearly opaque of faint peculiar d o u r almost tasteless soft elastic tenacious and adhesive to dr ON THE COMPOSITION OF JAPANESE BIRD-LIME.269 surfaces and slightly lighter than water. It can be preserved in water for an illdefinite time without change except on its upper surface. Exposed to air it very slowly turns brown outside and becomes coated with a thin brittle skin. If heated moderately it gives off water and above 100" froths from disengagement of steam. By the loss of its moisture it becomes transparent brown, and while hot of the consistency of cold oil. If now allowed to cool, it remains transparent and forms a soft solid mass elastic tenacions, and sticky as before somewhat resembling Canada balsam in appear-ance. Ether carbon bisulphide chloroform light petroleum and benzene dissolve bird-lime leaving a residue which although of not inconsiderable volume is of little weight.Cold alcohol scarcely dissolves it a t all and even hot alcohol which has some solvent action a t first attacks merely the surface-portion of the mass. The alcoholic solution as it cools deposits a nearly colourless transparent, adhesive matter differing but little from the purified bird-lime itself. Ether is much to be preferred to other solvents because it yields a clear solution whereas carbon bisulphide and the rest give milky liquids owing t o the presence of water. The ether solution mixed with alcohol becomes turbid and deposits a tenacioixs mass. Freed from water and particles of woody fibre bird-lime undergoes scarcely any change when heated up to temperatures below 350° merely becoming slightly fluorescent and a little darker in colour and acquiring a feeble waxy odour.About the melting point of zinc, however it uudergoes destructive distillation in which most of it comes over as fatty acids and fluorescent hydrocarbons of waxy and mild empyreumatic odour and buttery consistence ; very little per-manent gas is formed and only a small carbonaceous residue is left. Bird-lime burns in the air with a bright smoky flame. h'ulphuric acid dissolves it slowly forming a red liquid which blackens only when heated and which when poured into water gives a viscid precipitate like bird-lime but dark-coloured. Boiling nitric acid slowly dissolves it with partial oxidation this solution also yields a precipitate with water.The sulphuric acid solution poured into concentrated nitric acid, and then diluted with water yields a precipitate of it mixture of feebly nitrated compounds. Aqueous solutions of potassium hydroxide only slowly and slightly emulsify bird-lime ; fusion with the hydroxide is attended with much darkening in colour and leaves a mass which emulsifies in water. Potassium hydroxide in strong spirit slowly dis-solves the greater part of purified bird-lime producing a dark-coloured solution. I n this way,-that is by continued boiling with strong alcoholic potash-bird-lime has been attacked by both Personne and ourselves in order to determine its composition. It is not very sensitive to reagents. T 250 DIVERS AND KAWAKITA ON THE The Constituents of BiT-d-lime.Personne has found bird-lime prepared from I. nquijolium t o con-tain water 27 and vegetable de'bris and calcareous salts 23 parts per cent. tlhe remaining and essential part being some caoutchouc the compound ether or ethers of a new alcohol ancl other matters un-determined. The acids o r acid forming the ethers were also not investigated by him. He isolated the caoutchouc by saponifying the ethers with alcoholic potash which left the caoutchouc un-dissolved. Japanese bird-lime is much cleaner than that described by Per-some containing only 2 per cent. of dry-bark fragments and no separate lime salts. Its water content however is larger (probably because it is kept in stock under water) the percentage lost at 110-120" being 38.Caoutchouc forms about 6 per cent. leaving 54 per cent. as the proportion of compound ethers and allied mat,ters. The Bark &.-Of the 23 parts per cent. found in French bird-lime by Personne some 13 parts consisted of calcium oxn1ate.x On boiling out the bark fragments from Japanese bird-lime with sodium carbonate some oxalate was dissolved out but only in emall quantity. The bark burnt t o ashes gave as much as 6.3 per cent. of ash prin-cipally calcareous and largely phosphate but of course with some carbonate ; but as the whole ash was only one-eighth per cent. of the entire bird-lime and as only a little of the calcium salts was oxalate, Japanese differs in this respect remarkably from French bird-lime. The Caoutchouc.-As we have stated the caoutchouc can be sepa-rated by boiling out the purified bird-lime with alcoholic potash and this is the best way of proceeding.It is however difficult to get it quite free from potash and to this end needs to be repeatedly dis-solved in ether and reprecipitated by alcohol. The caoutchouc can also be separated by dissolving the bird-lime in ether and pre-cipitating the solution with 95 per cent. spirit but then only very imperfectly because the main constituent of the bird-lime is also pre-cipitated in part. The caoutchouc of bird-lime is pale-yellow and transparent highly elastic and when heated evolves the well-known penetrating odour. A combustion gave carbon 86.56 and hydrogen 11-31 per cent. so that oxygen to the extent of 2 per cent. was present.Before weighing it out it had been kept for some time at 120-130". It left a trace of ash when burnt. Other and Priwipal Constituents of Bird-lime.-We have not fully isolated these by proximate analytical methods but their general * Not phosphate aa stated in the abstract of Personne's paper in this Journal (46 1365) COMPOSITION OF JAPANESE BIRD-LIME. 2 i 1 pi-operties appear to be those of the partially purified bird-lime ; for when a boiling alcoholic solution of bird-lime is evaporated and cooled, or again when an ethereal solution of bird-lime is mixed with a little alcohol to separate the caoutchouc and then evaporated in either case the solid matter obtained is like the partially puritied bird-lime except in being colourless when deposited from the alcoholic solution.Products of the XaponiJication of Bird-lime and their Isolation.-Saponification with alcoholic potash yields besides the residual caout-chouc firstly the potassium salt of palmitic acid and a very little of that of a semi-solid acid which we have been unable to purify or identify ; secondly two crystalline alcohols; and thirdly a small quantity of a resinozd substance. The separation of these may be carried out in somewhat different ways and is unavoidably tedious. The purified bird-lime is boiled for two hours with potash and 95 per cent. spirit in a flask fitted with a reflux condenser ; and the alkaline solution decanted from the caoutchouc is poured into dilute spirit, by which a voluminous gelatinous precipitate is produced consisting of the alcohols with some of the resinoid body and potassinm palmi-tate.The precipitate is well broken up by stirring collected on a cloth filter pressed and washed with dilute spirit. Three ways of proceeding from this point have been employed by us. In one the precipitate is diffused through dilute spirit stirred well and warmed with calcium chloride solution. The now much less voluminous precipitate is repeatedly washed with water dried, and extracted with ether which leaves the calcium palmitate undis-solved. Spirit of 95 per cent. may be used in place of ether but as it dis-solves out a little calcium salt its use is less satisfactory. On evnporat -ing the ether (or spirit) the alcohols and resinoid body are obtained. A second way of proceeding is to warm the precipitate with water and hydrochloric acid until it has shrunken to a small volume wash repeatedly with water press moderately and extract with light petroleum which dissolves out the palmitic acid and some of the resino’id substame and leaves behind all the alcohols and the rest of the resino’id substance.After treatment by either method the resinoid compound is separated by repeated extractions with warm 80 per cent. spirit. A small quantity of the alcohols at the same time dissolves and may be partly recovered by precipitation with a very little water and extracting the precipitate with 80 per cent. spirit. The third way of proceeding which is simpler in exicution than the others but much less effective is to use 70-80 p;.r cent. spirit in place of the light petroleum in the second way of working.This dissolves out the resino‘id substance as well as palmiti acid. Personne’a method of procedure is to pour the product e,f saponifi 2'12 DIVERS AND KAWAKITA ON THE cation into water to wash the precipitate with much water treat it with acetic acid to neutral reaction again wash dry dissolve in hot 90 per cent. spirit cool and crystallise out the bird-lime alcohol from the solution. We have not found this method to work well on account of the great difficulty in washing properly the voluminous gelatinous precipitate and in just neutralising it with acetic acid. This precipitate contains besides the alcohols and resinojid substance, much acid potassium palmitate to which indeed its bulky natnre is partly due and we have found it far preferable to convert the potas-sium palmitate either into the calcium salt or into free acid as above described.Personne seems not to have recognised the presence of any fatty salt in the precipitate containing the alcohols. Separation of the Alcohols fyom each other and their Puri$cation.-The crude solid alcohols can only be fully separated from each other by fractional extraction with strong spirit repeated until the products obtained are of constant melting point. The alcohols already treated as described with 80 per cent. spirit to remove the resinoid substance, are warmed with successive portions of spirit increasing in strength from about 85 per cent. t o over 90 per cent. each portion of the solvent depositing crystals of the alcohols as it cools and each mother-liquor by successive evaporations yielding a series of other crystalline deposits all similar in appearance.When the last mother-liquors are too small in quantity and too impure to yield a satisfactory product by further evaporation they arc rejected or worked up for the little resino'id substance they contain. The portions of the alcohols least soluble in spirit consist principally of the one alcohol and those most soluble of the other alcohol. By a repetition of the treatment with Epirit the intermediate portions yield other series of deposits of higher and lower degrees of solubility the extremes of which contain the two alcohols. The portions of the less soluble alcohol are sub-mitted to further fractionation until the part undissolved by hot 90 per cent.spirit and that dissolved and deposited by it on cooling have the same melting point. It is then finally dissolved in hot 95 per cent. spirit crystallised out and again tested as to its melting point. The most soluble crystalline deposit consisting principally of the more soluble alcohol requires much further fractionation in order to separate the less soluble alcohol on the one side and the resinoi'd substance on the other so that the ultimate yield of the pure alcohol becomes very small. In fractionating out this alcohol spirit of 85 per cent. i! used but finally this alcohol like the other should be crys-tallised out from 95 per cent. spirit in order to get good crystals. Personne observed the comparative insolubility of the solid alcohol in 80 per ;ent.spirit but making no use of this fact he purified the cake of crude solid alcohol by repented crystallisations from boilin COMPOSlTlON OF JAPANESE BIRD-LIME. 273 90 per cent. spirit. During the piirification he met with a sub-stance of peculiar form visible under the microscope and less soluble in spirit than the solid alcohol and this he found to be gradually removed by repeated crystallisation. We have met with no such substance in Japanese bird-lime. Puri$ication of the Resinoid Compound.-This is found mainly in the 80 per cent. spirit used to wash the crude alcohols after they have been separated from palmitic acid. When this separation has been effected in the second way the spirit contains some fatty acids also.The light petroleum used to dissolve out palmitic acid also contains some of the resino'id substance. I n order therefore to separate palmitic acid the residue after evaporating the petroleum spirit is dissolved in alcoholic potash the palmitic acid precipi-tated by calcium chloride water added and the precipitate washed, dried and extracted with ether On evaporating the ether the resinoid substance is left still mixed with some of the alcohols but free from any fatty acid. The inipure product is dissolved in strong spirit, and left to evaporate slowly. The alcohols separate as indistinctly crystalline opaque matter while the resin separates on the bottom and sides of the vessel as a translucent gummy deposit still contain-ing spirit ; the resin is then redissolved in spirit and the solution left t'o evaporate for two hours.On repeating these operations several times it is obtained in a condition in which it has no longer any tendency to deposit crystalline matter. Separation and Pura3cation of the Fatty Acids.-By far the greater part of the fatty salts remain dissolved when the saponified bird-lime solution is poured into dilute spirit. The filtrate and washings from the gelatinous precipitate of alcohols are diluted with water mixed with hydrochloric acid and warmed in order to separate the fatty acids. By similar and well-known methods the portions of these acids thrown down along with the bird-lime alcohols can be recovered after separating them as calcium salts from the alcohols and resinoid substance and added to the main quantity.The crude fatty acids which when cold form a soft brown solid mass are dis-solved in alcoholic potash and precipitated again with calcium chlo-ride ; the calcium precipitate is washed with spirit which removes chlorides and some colouring matter as well as some of the calcium salt of the soft fatty acid ; the precipitate is then washed with ether, as this dissolves out most of the remaining colouring matter and calcium salt of the soft fatt'y acid more easily than spirit does ; lastly, it is heated with hydrochloric acid and water in order to get the crude palmitic acid. On repeating these operations once or twice and finally crystallising the product from spirit the palmitic acid is obtained in a pure state. By appropriate treatment the spirit and ether washing 274 DIVERS AND KAWAKITA OX THE of the calcium precipitate yield the semi-liquid acid although in an impure condition.Palmitic acid can also be prepared from bird-lime by destructive distillation. Its purification from hydrocarbons by means of saponifi-cation presents no great difficulty and need not be described. The Alcohols of Bird-lime. To one of the two alcohols of bird-lime we give the name mochylic cclcohol formed from the Japanese word nzochi for (bird-)lime or glutinous matter ; and to the other we attach the name i l k ~ l i c alcohol, essentially the same as ilicic alcohol given by Personne to the single alcohol described by him but framed more in accordance with the accepted nomenclature for alcohols. Our ilicylic alcohol differs but little from Personne's ilicic alcohol.Both the alcohols of bird-lime are obtained in tufts of small slender lustrous prisms and are dis-tinguishable from each other only iu solubility in melting point and in composition. -Wochylic alcohol occurs much more abuudan tly than ilicylic alcohol. It dissolves well in 95-98 per cent. spirit but is almost insoluble in 80 per cent. spirit. It is very little soluble in light petroleum i n the cold is readily soluble in ether and dissolves also in con-centratted sulphuric acid to which like bird-lime itself it imparts a red colour. It melts a t 234" and under atmospheric pressure decomposes a t a little below the melting pdint of zinc the principal product being a viscid matter apparently t(he hydrocarbon to be described among the products of the destructive distillation of bird-lime.In a vacuum it sublimes slightly at a little above 160" and freely and entirely near and above its melting point without decom-posing or changing in melting point. Heated with palmitic acid in a sealed tube a t 150-160" it yields a substance indistinguishable from bird-lime in essential properties a sticky transparent matter readily soluble in ether but nearly insoluble in the strongest spirit. Our attempts to obtain mochyl acetate by the action of acetic oxide or chloride have been unsuccessful. Ilicylic alcohol differs from mochylic alcohol in melting a t 172" and in being moderately soluble in 85-90 per cent. although almost in-soluble in 80 per cent. spirit. It begins to volatilise in a vacuum below 150" and sublimes freely near its melting point in beautiful t u f t s of needles still melting a t 172'.Heated with palmitic acid it also forms a substance like bird-lime. It fails apparently to yield an acetate even after long heating at 150-170" with acetic oxide in which when hot it as also mochylic alcohol readily dissolves partly crystallising out again unchanged on cooling and partly becoming COMPOSITION OF JAPANESE BIRD-LINE. 2 i 5 dark viscid matter not the acetate. Personne found that his ilicic alcohol when treated with acetic oxide yielded a crystalline acetate melting at 204-206". The melting point of Personne's ilicic alcohol was 175" and its boiling point above 350° but under a reduced pressure of 100 mm. it began to sublime a t 115".I n appearance and in behaviour to spirit of different strengths it was like our ilicylic alcohol. Both mochylic and ilicylic alcohols dissolve in a mixture of sulphnric and nitric acids and from the solution water separates a gelatinous matter readily soluble in spirit and deflagrating only slightly when dried and heated. C7aeinical Comnpositdon. of the Two AZco7ioZs.-Combustion of the two alcohols has given us the following results :-Mochylic Alcohol m. p. 234". Carbon 83.37 83.39 83.28 83.42 Hydrogen . 12.29 12-16 12.38 12.30 - 4.28 100-00 I. 11. 111. C26Ir4 6 0 -Oxygen. - - Ilicylic AZcoh01 m. p. 1.72". Carbon 83.09 82.98 83.02 Hydrogen . . . . . . . 11-93 11.92 11.95 Oxygen - 5-03 100*00 I. 11. C,,R,,O. --Ilicic Alcohol m.p. 175" (Personne's Analyses). Carbon . . 83.25 83.64 83.48 83.07 83.40 83.36 83.33 Hydrogen 12.18 12.44 12.17 12.24 11.98 12.20 12.22 - 4.45 I. 11. 111. IT. V. Mean. C2,H,,0. Oxygen - - - - -100*00 It will be seen that Personne's numbers vary rather widely but fall for the most part between those obtained by us for our two alcohols. It mill alsobe seen that the formula he has proposed as agreeing best with the mean of his analysis is thak of a homologue of our alcoho!s, the general expression being C,H,,-,O. As he worked on bird-lime from a species of Ilex different from that which yields Japanese bird-lime it cannot for the present be decided whether ilicic alcohol is distinct from the alcohols here described 276 DIVERS AND KAWAKITA ON THE The Resinoid Component of Bird-lime.The resinoild substance is obtained in pale-yellow fragments which are brittle and not sticky like bird-lime. It melts a t 110" and does not volatilise when heated to 220" in a vacuum. Above 360" it darkens boils and distils without much apparent change. It is very soluble in spirit even of 80 per cent. strength also in ether When its alcoholic solution is sufficiently evaporated by heat it separates from its solvent as a viscid liquid still containing spirit but this evaporates on further heating below 100". I t s solubility in spirit is not in-creased by the presence of potassium hydroxide. Heated with the solid hydroxide barely to the melting point it slowly combines with it probably a t the same time absorbing oxygen.The cooled mass wholly dissolves in water from which hydrochloric acid precipitates a gelatinous substance very brittle when dried. We have not further examined it for want of material. When bird-lime is kept for a long time a thin brittle skin forms on its surface which is readily soluble in spirit. This skin consists probably of the resino'id substance. If it does not then me have no evidence as to whether the resino'id substance is produced during the saponification of the bird-lime or exists in it ready formed as the result of slow atmospheric oxidation. In composition the resinoi'd substance differs from mochylic alcohol only in having two atoms less of hydrogen as the following analyses and calculation show :-I. 11. C26H440. Carbon 83.79 83.66 83.87 Hydrogen.. 11.80 11.92 11.83 Oxygen. . - 4.30 -100*00 The Fatty Acids of Bird-lime. The fatty acids of bird-lime are two as already stated palmitic acid and in small quantity only a semi-liquid acid the calcium salt of which is soluble in spirit and in ether. This acid haa not been further examined. The other shows all the characters of pnlmitic acid. Analysis of (I) acid prepared by saponi-fication and (11) acid obtained by destructive distillation of purified bird-lime :-Melting point 61.5" COMPOSlTION OF JAPANESE BIRD-LIME. 277 I. 11. Pslmitic acid. Carbon 74.98 74-86 75.00 Hydrogen . 12.67 12.55 12.50 - 12.50 Oxygen. . -100~00 The potassium salt yielded 13.3 per cent. of potassium. Products of Destructive Distillution. These have been already enumerated so far as their nature is known to us and the result of analysis of the palmitic acid has just been tabulated.The principal hydrocarbon distilling next after t'he palmitic acid was prepared from the middle portion of the distillate by treating it with hot spirit so as to leave about half of it undis-solved. This was then washed with cold spirit. The h-j-drocarbon thus left was a thick oil slightly yellow but not fluorescent. On analysis it gave numbers agreeing with the formula C26H44 :-Found. Calculated. Carbon 87.59 87.64 Hydrogen . 12-49 12.36 --100.08 100~00 Apparently the same compound is obtained by distilling mochylic alcohol under the ordinary atmospheric pressure. The decomposition of the main constituent of bird-lime by heat may therefore be thus represented :-Mochyl palmitate C,,H7,O = c2,& + C16H320~, and the decomposition of mochxlic alcohol by-C2J€46O = CJ344 + H20. The last fractions of the distillate consisted of hydrocarbons yielding No attempt was made to isolate the nearly 91 per cent. of carbon. caoutchouc-hydrocarbons no doubt present in the mixture. Comtitution of Bird-lime. Bird-lime is closely allied to the waxes and consists principally of mochyl and ilicyl palmitates C42H,60z and C&&&,. VOL. LIII.