Experimental Researches on the conductive Powers of various Sub- 543 On the Development of Carcinus Manas. By Spence Bate, Esq., F.L.S. 544 On the Electro-dynamic Qualities of Metals. By Prof. W. Thomson, F.R.S. On the Electric Conductivity of Commercial Copper of various On the Thermal Effects of Fluids in Motion. By Professor W. On the Thermal Effects of Longitudinal Compression of Solids. By 546 550 556 564 On the Phenomenon of Relief of the Image formed on the Ground Glass of the Camera Obscura. By A. Claudet, Esq., F.R.S... 569 Supplementary Researches on the Partition of Numbers. By Arthur Cayley, Esq., F.R.S... 573 On the Anatomy and Physiology of the Spongiada. By J. S. Bowerbank, Esq., F.R.S., F.L.S. &c. Researches on the Intimate Structure of the Brain; Human and 573 . 577 On the Early Stages of Inflammation. By Joseph Lister, Esq. . . 581 On the Fructification of certain Sphæriaceous Fungi. By Frederick Currey, Esq. 588 On the Anatomy of Tridacna. By John Denis Macdonald, Esq. 589 Experimental Researches on the Spinal Cord as a leader for Sensibility and Voluntary Movement. By E. Brown-Séquard, M.D.. 591 On the Resemblance of the Effects of Section of the Sympathetic Nerve in the Neck and those of Section of a lateral half of the Spinal Cord. By E. Brown-Séquard, M.D. . . 594 On the Influence of Efforts of Inspiration on the Movements of the 596 On the Influence of Oxygen on the vital properties of the Spinal On Hourly Observations of the Magnetic Declination, made by Captain 610 ᎬᎡᎡᎪᎢᎪ . Vol. VII. 6 from bottom, dele half. 4, for 2,000,000 read 5200×106; and for 8,200,000 read 21000 × 106. 10, for 10 tons read 53600 × 106 tons; and for 42 tons read 874000 x 106 tons. Vol. VIII. 8, for property read quality. 8, for a given result read given a result. 12, for that read steel. 11, for sine read cos 0. 3 from bottom, for p2-(§) read — 2 (E). 2 for (0)+2(0) read (0)-2(0). 10, for no read or without. 11 from bottom, dele Hence. 8 and 7 from bottom, for at the rate of one turn in 8 13, for the part read the narrow part. Q a 2, for 268° read 238°. 3, for 19° read 49°. 5, for ' read O'n ̧ 5, for (tan) read (tan). 7, for '-i read ə'n-i ̧ 2 13, for (sin 0)—2i−1 read (sin 0)—' -2i-1. 573, 12 from bottom, for June 15 read June 18. for M.D. read Esq. 11, for P(1, 2, 3, 4, 5, 6,) 9 read P(1, 2, 3, 4, 5, 6)q. لله الله PROCEEDINGS OF THE ROYAL SOCIETY. January 10, 1856. ADMIRAL BEECHEY, V.P., in the Chair. In consequence of there not being a sufficient number of Fellows present, the Ballot for the question of the readmission of Mr. Sievier was postponed to the next Meeting. The following communications were read :— I. "On Insolinic Acid." By AUGUSTUS W. HOFMANN, Ph.D., F.R.S. &c. Received December 20, 1855. (Abstract.) In attempting to purify cuminic acid by boiling with chromic acid, I observed that this acid experienced, on the part of this reagent, a progressive alteration. By twenty-four hours' ebullition, cuminic acid is completely converted into an acid insoluble in alcohol VOL. VIII. B and ether, for which I propose the provisional name of insolinic acid; purified by the ordinary processes, this body furnished on analysis the following relations : but the analysis of the salts demonstrates that this formula must be doubled, insolinic acid being a bibasic acid. I have examined the following salts: When considered by itself, insolinic acid has but slight claims on the attention of chemists; but when viewed in connexion with other groups of bodies, it acquires increased interest. Some years since, Gerhardt pointed out that to the homologous series of monobasic fatty acids Cn, Hng O4, the lowest terms of which are formic and acetic acids, there runs parallel a homologous series of bibasic acids, Cna Hna-2 O, the simplest member of which is oxalic acid. These two series of acids are connected by the closest ties, and very conclusive experiments have demonstrated that the members of the former may be easily converted into those of the latter; such is the case of the transformation of butyric into succinic acid, effected by M. Dessaignes under the influence of oxidizing agents. The following table exhibits these two series of acids arranged according to their carbon : The existence and the mode of formation of insolinic acid prove that to the series of monobasic aromatic acids, Cna Hn2-804, the lowest known term of which is benzoic acid, there corresponds likewise a series of bibasic acids, Cn2 Hn2-8-2 O=Cn2 Hn2-10 Og. Of this series few members are at present known, but the group of aromatic acids is itself very imperfect and limited. The two series comprise at present the following terms: 8 If we take the carbon as the standard of comparison, it is evident that the bibasic insolinic acid corresponds to the monobasic acid, which stands between toluylic and cuminic acid. In addition to this unknown acid, toluylic acid only is represented in the series of bibasic acids. There are, in fact, two bodies which may be regarded as representatives of toluylic acid, namely, phthalic and terephthalic acids. Benzoic and cuminic acid are not yet represented. |