[350] Pharm. Journ., Jan. 20, 1894.
TABLE OF RESULTS, ARRANGED ACCORDING TO PER CENT. OF NICOTINE.
| Variety examined. | Nicotine per cent. | ||
|---|---|---|---|
| 1. | Syrian leaves (a), | ·612 | |
| 2. | American chewing, | ·935 | |
| 3. | Syrian leaves (b), | 1 | ·093 |
| 4. | Chinese leaves, | 1 | ·902 |
| 5. | Turkish (coarse cut), | 2 | ·500 |
| 6. | Golden Virginia (whole strips), | 2 | ·501 |
| 7. | Gold Flake (Virginia), | 2 | ·501 |
| 8. | “Navy-cut” (light coloured), | 2 | ·530 |
| 9. | Light returns (Kentucky), | 2 | ·733 |
| 10. | “Navy-cut” (dark “all tobacco”), | 3 | ·640 |
| 11. | Best “Birds-eye,” | 3 | ·931 |
| 12. | Cut Cavendish (a), | 4 | ·212 |
| 13. | “Best Shag” (a), | 4 | ·907 |
| 14. | “Cut Cavendish” (b), | 4 | ·970 |
| 15. | “Best Shag” (b), | 5 | ·000 |
| 16. | French tobacco, | 8 | ·711 |
| 17. | Algerian tobacco (a), | 8 | ·813 |
| 18. | Algerian tobacco (b), | 8 | ·900 |
It is therefore obvious that the strength of tobacco in nicotine varies between wide limits.
Twenty-five grammes (or more or less, according to the amount of the sample at disposal) of the dried and powdered tobacco were intimately mixed with slaked lime, and distilled in a current of steam until the condensed steam was no longer alkaline; the distillate was slightly acidulated with dilute H2SO4, and evaporated to a conveniently small bulk. This was made alkaline with soda, and agitated repeatedly with successive portions of ether. The separated batches of ethereal solution of nicotine were then mixed and exposed to the air in a cool place. This exposure to the air carries away ammonia, if any be present, as well as ether.
Water was added to the ethereal residue, and the amount of nicotine present determined by decinormal H2SO4, using methyl-orange as an indicator. One c.c. of decinormal H2SO4 represents 0·0162 gramme of nicotine (C10H14N2).
§ 330. Nicotine (C10H14N2).—Hexahydro dipyridyl (C5H4N)2H6, when pure, is an oily, colourless fluid, of 1·0111, specific gravity at 15°.[351] It evaporates under 100° in white clouds, and boils at about 240°, at which temperature it partly distils over unchanged, and is partly decomposed—a brown resinous product remaining. It volatilises with aqueous and amyl alcohol vapour notably, and is not even fixed at -10°. It has a strong alkaline reaction, and rotates a ray of polarised light to the right. Its odour, especially on warming, is strong and unpleasantly like tobacco, and it has a sharp caustic taste. It absorbs water exposed to the air, and dissolves in water in all proportions, partly separating from such solution on the addition of a caustic alkali. The aqueous solution acts in many respects like ammonia, saturating acids fully, and may therefore be in certain cases estimated with accuracy by titration, 49 parts of H2SO4 corresponding to 162 of nicotine. It gives on oxidation nicotinic acid = m(β) pyridincarbo acid C5H4N(COOH), and by oxidation with elimination of water dipyridyl (C5H4N)2, and through reduction dipiperydil (C5H10N)2.