March 31, 1892 J 



NATURE 



525 



current circuits. Assuming constant permeability and no eddy 

 currents, the value of C comes out o 07398 sin {kt - 90°), whilst 

 with eddy currents and some saturation 



C =o'079i I sin {kt - 69°-2) - 0-014796 cos 3 kt - 0*003695 cos S/f/. 

 Dr. Fleming said he was working on the subject of choking coils, 

 and had found tiiat, in closed-circuit transformers unloaded, the 

 real watts were about 07 times the apparent watts. This, on 

 the assumption of sine functions, would indicate a lag of about 

 45°. A similar rule for open-circuit transformers was much 

 needed. It was important to know what size of core and coil 

 was required to choke down to a given current. Dr. Sumpner 

 thought it better to treat the subject graphically rather than by 

 anal V sis, and described a construction whereby the fundamental 

 equations could be readily integrated. Prof. Perry said he had 

 reason to think that ordinary hysteresis curves were not applic- 

 able to transformers. By analysis of the experimental E.M.F. 

 and current curves, one could work backwards and find the true 

 hysteresis curves. 



Chemical Society, March 3. — Prof. A. Crura Brown, 

 F. R. S., in the chair. — An address was read, which it is proposed 

 to present to Prof. Bunsen, who has now been for fifty years a 

 foreign m-mber of the Society. — The following papers were 

 then read : — A rule for determining whether a given benzene 

 mono-derivative shall give a meta-di-derivative or a mixture of 

 ortho- and para-diderivatives, by Prof. A. Crum Brown and 

 Dr. Gibson. If a benzene mono-derivative be converted into a 

 di-derivative by replacement of a second atom of hydrogen in 

 the nucleus by a radicle of the same kind as the one already 

 present, the product may consist either of the meta-di-derivative 

 or a mixture of ortho- and para-diderivatives. The authors 

 suggest a rule for determining which of these two cases will 

 result in any instance. If the hydride of the radicle employed 

 is directly convertible into the corresponding hydroxide, the 

 meta-di-derivative will be obtained on further substitution by 

 the same radi.ile. If the hydride of the substituting radicle is 

 not directly oxidizable to the hydroxy-compound a mixture of 

 ortho- and para-di-derivatives will result. For example, when 

 the substituting radicle is chlorine, as in the case of mono- 

 chlorobenzene, hydrogen chloride not being directly oxidizable 

 to hypochlorous acid, the rule indicates that a mixture of ortho- 

 and paradi derivatives will be obtained on further chlorination. 

 Nitrous acid is readily converted by direct oxidation into nitric 

 acid, so that on nitration of nitrobenzene, meta-dinitrobenzene 

 alone should be produced if the rule be a correct one. In these, 

 as in the other cases cited by the authors, the rule is found to 

 hold good. — The relative orienting effect of chlorine and 

 bromine; (l) The constitution of parabrom- and parachlor- 

 anilijiesu I phonic acids, by H. E. Armstrong and J. F. Briggs. 

 Parachlorobromobenzene on sulphonation yields one sulphonic 

 acid, CgHj. Br. CI. ."-1O3H, possessing the constitution CI: SO3H : 

 Br = I : 2 : 4. The authors were unable to obtain two sulphomc 

 acids on sulphonating parachloraniline ; only one was produced, 

 which separates from its aqueous solution in three distinct forms. 

 This also holds true for the sulphonation of parabromaniline, 

 the sulphonic acids having the constitution CI or Br: SOgll : NHj 

 = 1:2: 4. — Note on anhydrides of sulphonic acids, by H. E. 

 Armstrong. When para-dichloro-, chlorobromo-, and dibromo- 

 benzene are treated with sulphuric acid containing about 20 per 

 cent, of sulphuric anhydride, sulphonic anhydrides are obtained. 

 These compounds probably owe their formation to the dehydra- 

 tion of the corresponding sulphonic acids first formed. — Contribu- 

 tions to the knowledge of the aconite alkaloids ; Part II. 

 The alkaloids of true ^C(7mjVw/« napellus, by W R. Dunstan and 

 J. C. Umney. The roots of true Aconitum napellus were 

 extracted with cold fusel oil. The solution so obtained was, 

 after some preliminary treatment, extracted with eiher. Two 

 alkaloids were thus extracted, and were separated by means 

 of their hydrobromides into a crystalline and a gummy alkaloid. 

 The former of these was found to be aconitine, whilst the non- 

 crystal I izable compound is a new alkaloid which the authors 

 term napelline. This alkaloid is soluble in eher and alcohol, 

 and has a very bitter taste, but does not give rise to the tingling 

 sensation so characteristic of aconitine. Its salts could not be 

 crystallized. By further extraction of the fusel oil with chloro- 

 fornt, aconine was obtained. The roots of true Aconitum 

 napellus, therefore, must be held to contain three alkaloids, one 

 of which, VIZ. aconitine, is crystalline, whilst two are amorphous, 

 viz. napelline and aconine. Indications have been obtained of 

 the presence of a fourth alkaloid, which is amorphous and 



NO. r 170, VOL. 45] 



closely resembles napelline. Aconitine is by far the most toxic 

 of the alkaloids contained in Aconitum napellus. — Contributions 

 to our knowledge of the aconite alkaloids ; Part III. The for- 

 mation and properties of aconine and its conversion into aconi- 

 tine, by W. R. Dunstan and F. W. Passmore. When pure 

 aconitine is hydrolyzed by heating it with water in closed tubes 

 at 150°, aconine and benzoic acid are obtained in accordance 

 with the following equation — 



CsjH^sNOij -f HjO = CaeH^NOi, -f <Z^\i^O^; 

 no picraconitine or methyl alcohol is obtained at any stage. 

 Anhydro-aconitine is formed by the interaction of aconine and 

 ethyl benzoate at 130°, leaving no doubt that aconitine is 

 benzoyl-aconine. Aconine yields a crystalline hydrochloride, 

 QsH^NOji, HC1,2H20, whose specific rotatory power 

 [a]D = - 7°7I. Pure aconine is a hygroscopic, brittle gum, 

 having the composition Cj6H4iNO]j, and the rotatory power 

 [ajo = -F 23'. Its solution reduces Fehling's solution and gold 

 and silver salts. Its aqueous solution is slightly bitter, and 

 gives rise to a burning sensation in the mouth. A crystalline 

 aconitine methiodide, C33'-r45NOi2,CH3l, and an amorphous 

 methydroxide, C33H45NOi2,CH3. OH, have been prepared. A 

 simple laboratory shaking appliance, devised by Prof, Dunstan 

 and Mr. Dymond, was exhibited at the conclusion of this 

 paper. — Note on the carbon deposited from coal-gas flames, by 

 W. Foster. The author quotes analyses of cokes obtained by 

 carbonizing sugar and starch. From the similarity in composi- 

 tion of these cokes to that of the soot obtainable from coal-gas 

 flames, he is of opinion that these substances are all formed by 

 somewhat similar chemical processes. — The volumetric estima- 

 tion of mercury, by Chapman Jones. The author has devised a 

 modification of the cyanide method of estimating mercury. — 

 Chromic acid, by Eleanor Field. Results are quoted showing 

 that the crystals obtained on cooling with ice a solution of 

 chromium trioxide saturated at 90° consist merely of the trioxide,. 

 Cr03, and not of chromic acid, H2Cr04, as stated by Moissan. 

 — The origin of acetylene in flames, by V. B. Lewes. The 

 author has sought to determine whether acetylene is the product 

 of high temperature change or of oxidation. The experiments 

 described consisted in passing hydrocarbon gases and mixtures 

 of such gases with others through a heated platinum tube. The 

 results obtained appear to point to acetylene being formed by 

 the action of heat alone. 



Geological Society, March 9.— W. H. Hudleston, F.R.S., 

 President, in the chair. — The following communications were 

 read : — The new railway from Grays Thurrock to Romford : 

 sections between Upminster and Romford, by T. V. Holmes. 

 In the Homchurch cutting of the new railway, boulder clay, of 

 which about 15 feet is seen, rests upon the London Clay 

 near the loo-feet contour-line, and is overlain by 10 to \z 

 feet of sand and gravel. The author gives reasons for inferring 

 that this sand and gravel belongs to the oldest terrace of the 

 Thames Valley gravel occurring in this district, and states that 

 it demonstrates the truth of Mr. Whitaker's conclusion that the 

 Thames Valley deposits are (1 cally) post-Glacial, or newer than 

 the local boulder clay. After the reading of this paper the 

 President said that geologists were much indebted to Mr. 

 Holmes for drawing attention to this interesting section before 

 it was too late. Amongst the many points arising from the 

 discovery of boulder clay at less than 100 feet above Ordnance 

 datum was one as to the probability of the pre- Glacial age of the 

 Thames Valley system. Mr. H. B. Woodward, Mr. H. W. 

 Monckton, Mr. C. Reid, Dr. Hicks, Mr. Lewis Abbott, and 

 Mr. Whitaker also spoke. — The drift beds of the North Wales 

 and Mid- Wales coast, by T. Mellard Reade. This paper is a 

 continuation of papers by the author on the drift beds of the 

 north-west of England and North Wales. The author first treats 

 of the Moel Tryfaen and other Caernarvonshire drifts ; he 

 describes the drifts of the coast and coastal plain, connecting 

 his observations with those of the Moel Tryfaen drifts. Aq 

 important feature of the investigation is the numerous mechanical 

 analyses of the various clays, sands, and gravels. In all the 

 samples but one, a large proportion of extremely rounded and 

 polished quartz-grains have been found, which the author 

 maintains to be true erratics, and a certain sign of marine 

 action. He shows that the Moel Tryfaen marine sands are in 

 part overlain by typical till, composed almost wholly of local 

 rocks with a small percentage of clay, whereas the sands and 

 gravels are full of erratics, including rocks from Scotland and 

 the Lake District, numerous flints. Carboniferous Limestone, and 



