150 Miscellaneous Intelligence. 



more in diameter, being selected, is to be closed at one end by the 

 blow-pipe ; and then, being softened near the other end, is to be 

 drawn out obliquely, so as to form the long narrow neck represented 

 in the wood-cut, but to which, in the first case, the short piece of tube 

 is to be left attached ; this forms a funnel, into which the prepara- 

 tion to be preserved is to be put. Then, warming the body of the 

 tube, the expanding air passes out through the fluid ; and, after- 

 wards, on cooling the vessel, the liquid descends into it. A small 

 spirit-lamp flame being now applied at the upper part of the long 

 neck, softens the glass, which is then to be drawn out to a fine 

 point and sealed. In this state the substance may be preserved 

 clean and pure for any length of time. 



If a small portion be required for an expe- 

 riment, the extreme point of the neck is to 

 be opened by pinching it off, the tube is then 

 to be inclined until the quantity required 

 has entered the neck, where, by capillary 

 attraction, it will form a small column, and 

 the tube being warmed by the hand, the at- 

 mosphere within it will expand and expel the 

 portion of fluid on to the place required. A 

 very little practice will enable the experi- 

 menter to judge of the quantity he is forcing 

 out, and in this way he may take a portion 

 not larger than the l-20th of a common drop, 

 or he may take the whole contents of the 

 tube. When the quantity required has been 

 taken out, the tube is to be placed in an up- 

 right position, and the flame of a lamp, or 

 candle, or even a piece of paper, closes the 

 aperture in a moment and as perfectly as 

 before. 



I have found these tubes very serviceable 

 when working with substance either very 

 small in quantity or obtained with great dif- 

 ficulty, in consequence of the entire preven- 

 tion of waste resulting from their use. They 

 are easily labelled by scratching the name of 

 the substance with a diamond on them, and 

 may conveniently be retained by putting se- 

 veral of them together into a tumbler, or 

 other glass of that kind. — M. F. \^_^ 



5. Supports f 07' Substances before the BloW'pipe. — Lieutenant- 

 colonel Totten has adopted a modification of Mr. Smithson's con- 

 trivance. He pulverises a portion of the mineral to be tried, 

 forms a paste of it with very thick gum- water, and rolling it under 

 the finger moulds it into an acute cone, sometimes nearly an inch 



