Transcriber’s Notes: Typographical and punctuation errors have been silently corrected. A Further Investigation of the Symmetrical Chloride of Paranitroorthosulphobenzoic Acid. Dissertation. Submitted to the Board of University Studies of the Johns Hopkins University for the Degree of Doctor of Philosophy. — by — William E. Henderson. 1897 Acknowledgment. The author esteems it a privilege as well as a pleasure to give expression to his sincere sense of gratitude to Prof. Remsen,under whose guidance this work was carried on not only for instruction received in the lecture room, but for his frequent suggestion, and his constant and friendly interest in the work as it progressed. These have at all times been an encouragement and an incentive. He wishes also to express his appreciation of the instruction and kindly guidance in the laboratory, of Drs. Morse and Renouf, as well as of Dr. Ames of the Physical Laboratory. Contents. I. Introduction. Page 1 II. Preparation of the Acid Potassium Salt of Paranitroorthosulphobenzoic Acid. 6 III. Preparation of the Symmetrical Chloride of Paranitroorthosulphobenzoic Acid. 12 IV. Properties of the Symmetrical Chloride of Paranitroorthosulphobenzoic Acid. 19 V. The Action of Benzene and Aluminium Chloride on the Symmetrical Chloride of Paranitroorthosulphobenzoic Acid. 22 The Barium Salts of Paranitroorthobenzoybbenzenesulphonic Acid. 24 VI. The Action of Alcohols on the Symmetrical Chloride of Paranitroorthosulphobenzoic Acid. 30 1. Methyl Alcohol. 31 2. Ethyl Alcohol. 32 Action of Ethyl Alcohol on the Unsymmetrical Chloride. 36 VII. The Action of Phenols on the Symmetrical Chloride of Paranitroorthosulphobenzoic Acid. 38 1. Phenol. 40 2. Orthocresol. 48 3. Paracresol. 51 4. Hydroquinone. 53 5. Resorcin. 56 6. Pyrogallol. 59 7. β-naphthol. 61 VIII. The Action of Aniline on the Symmetrical Chloride of Paranitroorthosulphobenzoic Acid. 62