Note 405 — PHARMACOLOGIA. (continued 2)

In order to close the end of the tube, where a blow-pipe is not to be procured, the end is to be placed in a common fire, until it is completely softened, and a pair of small tongs being at the same time made red hot, the tube is to be withdrawn from the fire, and then heated and pinched by the tongs, and at the same time bent up at an acute angle, so as to be brought parallel to the body of the tube. The tube is then to be heated a second time, and being again firmly pinched by the hot tongs, the end will be found to be completely impervious. Where a glass is not at hand Mr. R. Phillips says a common draught phial may be made to answer the purpose, especially a ten drachm phial, for it is long in proportion to its diameter. In using it, however, care must be taken that the suspected powder and black flux do not reach the bottom, for, on account of its thickness, it will readily break on the application of heat. The phial must therefore be heated laterally by means of a spirit lamp.