io4 



THE A L UMN1 JO URNAL. 



with alcohol even for ten minutes lost 50 per 

 cent, of its alkaloidal power. At present there 

 was no direct authority for standardizing gener- 

 ally, but there was such a demand for standard- 

 ized preparations, and the result was that, in 

 the absence of official methods, each wholesale 

 house or each pharmacist, was left to fix the 

 standards, so that uniformity was not likely to 

 exist. Something was wanted more than mere 

 statements of percentages : the methods of 

 analysis should be well defined. Meyer's solu. 

 tion was out of date, and it was hardly settled 

 whether volumetric methods or gravimetric pro- 

 cesses should be followed; or even in some cases, 

 as that of aconite, if the test should not be 

 physiological. Messrs. Wright and Farr stood 

 pre eminent amongst British workers, and had 

 for several years been publishing the most im- 

 portant results, and he thought their methods 

 of assay might well be adopted. Various stand- 

 ards had been suggested, but in most cases of 

 average good drugs, but the author of the paper 

 had met with a practical difficulty which re- 

 quired some consideration. It was, that it was 

 not difficult to obtain drugs frequently above 

 any average that might be fixed, and the ques- 

 tion arose— Should we use less to produce a 

 preparation of "average" strength ? He thought 

 not, as the Pharmacopoeia distinctly ordered a 

 definite weight to be taken, so that for the pres- 

 ent, at least, he ventured to suggest that the 

 standard adopted should be that approximating 

 to the highest percentage. Concentrated tinc- 

 tures might receive some attention at their 

 hands. They were more properly described as 

 fluid extracts, and experience had shown that 

 fluid extracts prepared with proof spirit, at 

 least, were somewhat unstable. So that it might 

 be asked what strength of spirit should be used 

 for exhaustion. As an example, they had Tinct. 

 Catechu, and to produce a concentrated tincture 

 four times the ordinary strength, it was required 

 to dissolve or exhaust 10 ounces, of catechu, 

 with sufficient proof spirit to produce one pint 

 of finished liquid. Could a permanent and satis- 

 factory preparation be so made. Again, capsi- 

 cum formed a tincture in which an excess of 

 spirit might appear to be used for exhaustion 

 but the dose being small, it was probably better 

 for dispensing purposes than a stronger tincture 

 given in smaller amounts. If concentrated 

 tinctures were used, let them be employed for 

 special .purposes rather than for the preparation 

 of the official tinctures.— Brit, and Col. Drug, 

 1894, 489. 



MANUFACTURE OF ESSENTIAL OILS. 



The essential oil industry has derived 

 considerable advantages from the pro- 

 gress in the chemical investigation of es- 

 sential oils. The term which used 

 often to be applied to the supposed work- 

 manlike manufacture of an essential oil, 

 that it had been turned out according to 

 the rules of the art {lege artis) is now no 

 longer suitable. A mode of manu- 

 facture based upon intelligent prin- 

 ciples has replaced rule - of- thumb 

 work ; craftmanship has been ousted 

 by science, which, in teaching us 

 the physical and chemical properties of 

 an oil, indicates at the same time ways 

 and means of improving its manufacture. 

 Nowadays each raw material requires its 

 own method of distillation, every crude 

 oil its own special mode of rectification. 

 The processes of preparing similar oils 

 are sometimes altogether different in 

 principle, while in other cases slight de- 

 viations in method are sufficient to bring 

 about important improvements in the 

 manufacture. The fact that freshly 

 distilled oils have a disagreeable sub- 

 sidiary odor, the so-called "still smell," 

 was formerly looked upon as quite 

 a matter of course, but it is now 

 known to indicate either want of 

 knowledge in the process of distillation 

 or gross carelessness. The fresher the 

 oil, the purer should be its odor and 

 taste. Freshly rectified oil of caraway 

 should smell just, as aromatic and agree- 

 able as the freshly crushed seed. If, as 

 a result of defective distillation, an oil 

 has once acquired the well-known 

 mouldy sharp odor, no amount of ex- 

 posure of the oil to the air will remove 

 this entirely ; but, on the other hand, 

 the oil, if kept in this condition, all the 

 more rapidly falls a victim to the fate of 

 almost all essential oils, viz., resinifica- 

 tion or other decomposition, without hav- 

 ing ever been really pure in odor or taste. 

 — SchimmeV s Bericht, 1894. 



