190 THE ANALYST. THE APPLICATION O F CHLOROFORM I N THE TESTING OF DRUGS. BY L. SIEBOLD, F.C.S. In the ‘ Year-Book of Pliarmacy ’ for 1877 there occurs an abstract of an article by Dr. C. Himly on tlie Detection of lfineral Adnltsrants 111 Yloiir by means of Chloroform. Having frequently tried this test and finding it extremely useful both as n qualitative and as a qmntitativc process, it appeared to ine desirable to ascertaiu to what extent it might be advantageously employed in the testing of powdcred vegetable drugs.As many of the latter are liglitcr tlinii cliloroform, aid the usual mineral adulterants sink in that liqiiicl, it m s but reasonable to infer that this mode of seyaratioii might prove of ndue to the pharmacist. I will not trouble tlic meeting with the details of my experiments, but confine myself to a, brief summary of the results, In each experiment (?I small quantity of the dry powder mas well shalreii witli about half a test-tubeful of chloroform, and the mixture allowed to stand at rest for twelve hours.The following drugs were found to rise so completely to the surface of the chloroform, that the observation and estimation of any mineral adulterant became a very simple and easy task :-Acacia, tragacanth, starches, myrrh, Barbadoes aloes, jalap, saffron, cinchonas, nux vomica, mustard, white pepper, capsicum, aiid guarana.Known quail tities of selenite and of chalk were added to these drugs, and subsequently determined by running tlie lower stratam of the chloroform with the sediment into a small dish, carefully pouring off the chloroform, drying the sediment at a gentle heat and weighing it.The result in each case was very satisfactory. No such accuracy could be attained by incineration, as in the presence of clialk there was always n loss of carbonic acid, anctin that of selenite a loss of water and of oxygen, the sulphate being partly reduced to sulphide. An estimation of these adulterants by the usual analytical processes would, of course, give exact results, but prove much more tedious.Both for qualitative and for quantitative purposes, the chloroform test thereforeTHE ANALYST. 191 answers extremely well with tlie drugs named. In the case of the following substaiices no complete rise to the surface of the chloroform took place, but a portion was found to float and another portion to sink, though the absence of mineral adulterants was proved by analysis :-Gamboge, scammony, opium, Socotrine aloes, liquorice root, ginger, colocyn th, C O U S S ~ , ipecacuaiiha, cinnamon and cardamoms.Of the last two by far the greater portion was found to sink in chloroform. But even in these cases the test is not altogether without value, for a careful inspection of the sediment will show whether or not it is a mixture of various substances, differing in appearance, weight, kc.The mineral adulterant will generally, in such a case, form the lowest stratum of the sediment. A comparison witli a genuine sample helps to arrive at a correct conclusion. Moreover the chemical examination of the sediment gives results which cannot always be obtained by testing the ash.Take the case of cinnamon, for instance, wliich contains organic calcium salts. These upon incineration leave calcium carbonate, a i d a qualitative analysis of the ssh would therefore fail to show whether this calcium carbonate was solely the result of ignition, or whether n part of it pre-existed in the cinnamon powder as an adulterant ; while the addition of hydrochloric acid to the lowest stratum of the chloroform sediment would settle this point at once. It is, however, in the case of the drugs first iiamed that I wish specially to recommend this mode of testing to pharmacists,