For the chymical part I have principally consulted the last editions of the System of Chemistry of Dr. Thomson, and that of my very ingenious friend Dr. Murray; the Annales de Chimie et de Physique; the Philosophical Transactions; and the best chemical papers inserted in the periodical publications; nor have I refrained from taking advantage of the observations of Dr. Duncan contained in the Edinburgh New Dispensatory.1 As this is undoubtedly the most important part of the work, I have given it all the attention I am possessed of; and although it would be almost impossible, and altogether unnecessary, to prove by actual experiment the correctness of all the formulas for the preparations and compositions ordered in the Pharmacopoeias, yet the greater part of those ordered in the London Pharmacopoeia, which I have chosen for my text book, have been repeated, and an unrestrained opinion regarding them delivered. Those chemical theories only, however, which are fully established have been adopted; and I have studiously avoided ranking myself on either side, on the important questions now at issue, suggested by the late investigations of Mr. (now Sir. H.) Davy.1

1 The following are the more important of the additional works which have also been consulted: -

Flore du Dictionnaire des Sciences Medicates, decrites par F. P. Chaumeton, Chamberet et Poiret. 8vo. Paris.

Histoire Nat. ed Mid. des Cases, etc.: L. T. Calloden de Geneve, M.D 4to. Montpelier, 1816.

Materia Medica of Hindostan, etc. etc. By Whitelaw Ainslie, M.D. 4to. Madras, 1813.

A Treatise on the Medicinal Leech, etc. etc. By T. Johnson, M.D. 8vo. London.

The author, in addition to the above works, has used freely the elementary volume of his late friend and colleague Dr. Ed. Turner; Drs. Trousseau et Pidoux, Traiti de Therapeutique, 8vo. tomes ii. Paris, 1837, and Journal de Pharmacie.

Mem. de la Societe Imperiale des Nat. de Moscow, 4to. Moscow, 1809. Asiatic Researches. 4to. Calcutta.

With regard to the reformed nomenclature of the Pharmacopoeias, the entire principle of which has been strongly objected to by Dr. Bostock, in his Remarks on the Nomenclature of the London Pharmacopoeia, I conceive it to be my duty to state here, that although I have not scrupled freely to criticise such names as appear to me to be improper in the work of the London College, and incompatible with the views of the subject which it professes to have taken, yet I do not concur with that gentleman in thinking that the reform was unnecessary, or now, when it is accomplished, that it is not likely to be generally adopted. It is, indeed, deeply to be lamented, that a work issuing from so respectable and learned a body as the London College is acknowledged to be, is not more perfect in its execution: but, nevertheless, its nomenclature is much superior to that of its predecessor; and within the scope of my own observation, as well as from information which I have received from others, it is now coming into very general use.

Many of the older physicians already write their prescriptions in the reformed language; and it is so congenial with the habits of thinking, and the ordinary language and mode of writing of the younger practitioners, that there is no doubt of its being readily adopted by them.1

Tableaux Chimiques du Regne Animal, etc. par Jean-Frederic John. etc. traduit de l' Altemand, par Stephane Robinet, 4to. Paris, 1818.

Annates de Chimie et de Physique, 8vo. Paris.

Henry's Elements of Experimental Chymistry, 7th edit. 8vo. London.

Elementidi Chimica Earmaceutica e d'Istoria Naturale, etc. 8vo. Torino.

Nouveaux Elemens de Therapeutique et de Matiere Medicale, etc par I. L. Alibert, 8vo. 4me, edit. Paris, 1817.

Earmacopea Generate ossia Dizionario delle Preparazioni Earmaceutico-Mediche, etc. di L. V. Brugnatelli, 8vo. Pavia, 1814.

Traite des Poisons, etc. etc. par M. P. Orfila, 8vo. Paris,

Phillips's Remarks on the Editio Altera of the Pharm. Lond. 8vo. London.

Journal de Pharmacie et des Sciences Accessoires, etc. 8vo. Paris.

Journal of Science and the Arts, 8vo. London.

The Annals of Philosophy, 8vo. London.

Medico-Chirurgical Transactions, 8vo, London.

The London Medical Repository, 8vo. London.

Bancroft's Philosophy of Permanent Colours, 2d edit. 8vo. London.

Lambert' s Illustrations of the Genus Cinchona, 4to. Lond. 1821.

Rurckhardt's Travels in Nubia, 4to. Lond. 1820.

Davy's Account of the Interior of Ceylon, 4to. Lond. 1821.

Humboldt's Personal Narrative, 8vo. Lond. 1821.

Opium Historice, Chemice atque Pharmacologice Investigatum, per C. A. Christen, 8vo. Vind. 1820.

Pharmacologia, etc. etc. : 3d edit. 8vo. Lond. 1820.

Pharmacopoeia Ralava ct Notis, etc. Lipsiae, 1824.

1 The establishment of Sir H. Davy's theories has rendered the reserve implied an this sentence no longer necessary.

The best authors have been consulted regarding the medicinal properties and uses of the various substances treated of; but I must confess that less attention has been given to this, as it is not intended that the practice of medicine should be taught by a Dispensatory; and surely little is to be expected from those who would attempt to acquire it from such a source. As memorandums, however, I have been anxious to make the medical notices as correct as possible; and have, in most instances, given references to the works from which the best information on this part of the subject may be obtained.

After all my efforts, however, to avoid errors, I am sensible that the work may, nevertheless, contain many; I have, therefore, determined to lend a willing ear to the remarks of candid criticism; and, in future editions, to take advantage of every suggestion that may tend to bring it nearer to that state of perfection, the attainment of which must afford more satisfaction to an author than all the indiscriminate praise which can be lavished upon his labours. I might, indeed, plead as an apology for its imperfections, that the work has not been prepared in the repose of retirement, and with an abundance of leisure; but, on the contrary, that I have been able to bestow on it the few leisure hours only which I could snatch from full employment in a laborious branch of the profession, and during the wasting of the midnight oil, amidst inconvenience and anxieties; and with the perpetual annoyance of professional interruptions. I am sensible, however, of the futility of such an apology; and as the book is now in the hands of the profession, it must fall or rise according to its merits.

I can only hope these will be justly appreciated by the Public, that tribunal, by which every production, whether of intellect or of labour, must be ultimately judged.

1 The experience of years has fully confirmed these anticipations.

Anthony Todd Thomson.

91. Sloane Street, April, 1811.

Explanation of the abbreviations employed in the synonymes; and the chymical symbols.

(F.) French. (G.) German. (I) Italian. (S.) Spanish.

(Dutch) (Swed.) Swedish. (Dan.) Danish. (Pol) Polish. (Port.) Portuguese. (Russian.) (H.) Hindoostanie. (San.) Sanscrit. ( Tam.) Tamool. (A.) Arabic. (Pers.) Persian. (Beng.) Bengalese. (Duk.) Dukhanie. (Malay.)

(Cyng.) Cynghalese. (Celebes.) (Jav.) Javanese. (Esqui.) Esquimaux. (Chin.) Chinese.

Chymical Symbols.

Aluminium (Al). Ammonia (Am). Antimonium (Sb). Arsenic (As). Barium (Ba). Bismuth (Bi). Boron (B). Bromine (Br). Calcium (Ca). Carbon (C). Chlorine (Cl).

Copper (Cu). Cyanogen (Cy). Hydrogen (H). Iodine (I). Iron (Fe). Lead (Pl). Magnesium (Mg). Manganese (Mn). Mercury (Hy). Nitrogen (N). Oxygen (O). Phosphorus (R). Potassium (K). Silver (Ag). Sodium (Na). Sulphur (S). Water (Aq). Zinc (Zn).

Two equivalents of a substance may be denoted by a dash under the symbol

H. P. S. Compounds are marked as follows: - N nitric acid, S sulphuric acid, the dots above the symbol showing the quantity of oxygen in the acid: or K S-Ca C --sulphate of potassa, carbonate of lime. When there is more than one equivalent of the constituent of a compound, it is marked thus: - N H 3, ammonia; N C 2, cyanogen; H 3 C 2 O, alcohol. The vegetable acids are denoted by a dash over the first letter of their names: - A, acetic acid; B, benzoic acid; C citric acid, and so on.