MR. RIASKELYNE ON THE VI.-On the oxidation of Chinese @ragc BY NEPILS MASKELYNE, M.A. DEPUTY READER. IN MINERALO#Y TO THE UNIVERSITY OF OXFORD. The experiment which 1 propose to describe suggested itself in the course of an investigation commenced by me in the laboratory of Mr. Brodie in the early part of last year but which has been inter- rupted by unavoidable circumstances and only recently resumed. Without entering upon the other questions involved in that investi- gation it is only necessary to state that it embraced the inquiry into the chemical nature of the substances whicb we know as Chinese wax and spermaceti. When isolated froiz-r certain slight impurities which it contains Chinese wax has the formula CIo8HjosO, which by the action of hydrate of potash may be broken up into substances with OXIDATION OF CHINESE WAX.the formulze C, H, 0 [cerotin] + C, H, 0 [cerotic acid] two equivalents of water being assumed in the saponification. If instead of melting the Chinese wax with bydrate of potash with a view to saponify it it be mixed with lime and potash and heated gently in a large combustion tube a change takes place in the substance which is of a definite character and therefore easily controlled. Hydrogen gas is evolved at the part of the tube where the heat is applied; and so soon as this evolution ceases the coals should be removed to another part of it. The product resulting from this oxidation of the wax is as will be seen a salt of cerotic acid and if the process be carefully performed this forms a very neat indeed the best way of procuring this wax-acid.53 OZ. of potash-lime were taken to oxidize 1oz. of Chinese wax. The resulting mass was boiled for a long time with hydrochloric acid; the wax matter thus eliminated was then frequently boiled with water and finally dissolved in alcohol and filtered while hot. A little undissolved substance remains on the filter but it is only in very minute quantity. On the cooling of the alcohol the dissolved substance forms a copious white precipitate of which the melting point is 79°-800 C. The acid however is not pure; for here as is probably also the case with spermaceti there is present a contami- nating substance in small quantity which it is very difficult to separate completely.The mass of acid has to be dissolved and crys- tallized two or three times out of alcohol and finally once or twice out of ether. The ether holds in solution the substance alluded to which exists in very small quantity and has a melting point at least as low as 69'. The acid as thus obtained is pure cerotic acid. Its melting point is 8l0 82O and it yielded on being analyzed the following numbers I. 02332grms. gave *6771CO and ,2725 HO 11. *2110 , , a61 18 , *2536 111. another preparation *2355 , , 06814 , *2841 which correspond to the following per-centage of carbon and hy- drogen I. 11. 1x1. Theory requires. Carbon 79.19 79.07 78-90 79-02 Hydrogen 12-98 13.35 13.41 13.17 Oxygen 7.83- 7.58- 7.69 7-81 c11. 100*00 100*00 100~00 100~00 26 MR.MASKELYNE ON THE OXIDATION OF CHIXESE WAX. The silver-salt was formed by means of an alcoholic solution of nitrate of silver and a solution also in alcohol of an ammonia-salt of the acid in the presence of an excess of ammonia. It yielded the following per centage of silver 6.10 grs. gave 1.280grs. = 20.98 per cent 4.81 , , 1.010 , = 20.99 , Theory requires 20.90 , There can therefore be little question as to the character of the change thus wrought by the oxidizing action of the potash-lime. Regarding the wax as the homologue of acetic ether the acid has its origin in two sources. On the one hand the ether of which cerotin is the corresponding alcohol is oxidized into cerotic acid while on the other hand the anhydrous cerotic acid which on this view is sup- posed to be combined with that ether unites with the alkali the process being divided into two parts first the saponification of the substance and subsequently the oxidation of the alcohol formed from the ether by that saponiiication.On another view first propounded by Mr. Lawrence Smith in relation to spermaceti we may look upon these bodies as homologues of aldehyde in which case the wax may be regarded as the aldehyde of cerotic acid its formula being halved [Clog HIo80 = 2 (C,* H, O,)]. Regarding it in this light the oxidation is that of the substance as a whole into cerotic acid C, H, 0,+02=C5 H, 0,. The present experiment does not decide between these two views. I have made some further experi- ments in this direction which T hope on a future opportunity to communicate to the Society.The process I have described is im-portant as furnishing by far the most expeditious method we at present possess of procuring cerotic acid; for the washing out of the baryta-salt formed in the treatment of the Chinese wax or of the lead-salt of cerotic acid from common bees-wax is a most tedious operation. Spermaceti is a body precisely identical in type with Chinese wax. I have oxidized this substance also in the expectation that the result would elear up the doubt as to the identity or otherwise of ethalic and palmitic acids. These experiments do not belong to the history of Chinese wax and it will therefore be przferablt to make them also the subject of a future communication.MR. HERAPATH ON THE ESTIMATiON OF IRON. On a quick approximative method of estimating minute quantities of iron by means of a Calorimeter. BYTHORNTON J. HERAPATH. The author having been much occupied with the analysis of waters containing minute quantities of iron and finding the ordinary mocie of estimation by precipitation and weighing very troublesome and inac- curate when applied to such quantities was led to avail himself of the following centigrade method founded on the reaction of persalts of iron with sulphocyanide of potassium. A standard solution of per- chloride of iron containing a little less than -&-&h of a grain of metallic iron per cent was prepared by dissolving 1 grain of iron in hydrochloric acid with the addition of a little nitric acid evapo- rating nearly to dryness and diluting to 10,000 gr.measures with distilled water at 60°; and from this other standard soltitions of different strengths were formed. A convenient quantity of the water generally half a gallon was evaporated to dryness and the saline mass so obtained was afterwards dissolved in hydrochloric acid. The iron contained in the solution having been converted into perchloride by boiling with a few drops of nitric acid the silica and other insoluble substances were separated by filtration and the per- oxide of iron precipitated by ammonia. This latter precipitate was collected on a filter and well washed with water. It was then redissolved in the smallest possible quantity of hydrochloric acid and the liquid having been introduced into a phial or tube of known capacity was diluted with distilled water until it reached a particular mark upon the side corresponding to 1000 water-grain measures ; care being taken of course to add previously a few drops of a solution of sulphocyanide of potassium.The depth of tint was then com-pared with that of the standard solutions before mentioned contained in tubes or phials of similar diameter in which certain known quan-tities of iron ranging froin the T-&5th to the $th of a grain were contained in the same bulk of water. In order to render the com- parison of tints more perfect the tubes were placed against a sheet of white writing paper and held between the eye and the diffused light.Operating in this way the author was enabled to estimate the -i-T1mth of a grain of iron per gallon with the greatest readiness. It was sometimes found preferable to employ but one standard solution. The proportion of iron in the liquid tested was then determined by measuring the volume of water that was required to lighten the tint so as to render it identical with that of the normal solution or vice atersa". MR FORSTER ON METACETONIC ACID. OnDr. Keller’s* supposed formation of Metacetonic Acid from Flour and Leather. BYR. W. FORSTER. A mixture of flour with scraps of leather carbonate of lime and water having been digested for three weeks at a gentle heat the liquid was strained off the dissolved lime-salt converted into a soda- salt the solution concentrated by evaporation and distilled with excess of sulphuric acid.A portion of the acid distillate was then neutra- lized with carbonate of soda the remainder added to it and the whole distilled. According to Keller butyric ether should distil over acetate and metacetonate of soda remaining in the retort. The dis- tillate obtained by Mr. Forster however had an odour not at all resembling that of butyric ether ;and the dry residue when distilled with sulphuric acid yielded a distillate which had not the odour of either acetic or metacetonic acid and gave no odour of acetic ether when heated with alcohol and sulphuric acid. The liquid also yielded a baryta-salt containing 65.5 per cent (mean) of baryta a quantity differing by 1i per cent from 67.4 the amount required by the formiate ; the deficiency was probably due to slight impurities. Acetate of baryta contains 60 and metacetonate of baryta 5406 per cent of the base. Moreover the solution of the baryta-salt rapidly reduced nitrate of silver. The principal constituent of the distillate appears therefore to be formic acid. * See this Journal Vol. 111 p. 190.