83 



tube, apparently like water through a capillary siphon, and was 

 again found on the floor. 



On cutting the tube into pieces, it was evident that the mercury 

 had not passed along the hollow axis, but had, apparently, been trans- 

 mitted through the pores of the solid metal. To determine this, 

 a lead rod of about seven inches long and a quarter of an inch 

 in diameter, was bent into the form of a siphon. The shorter leg 

 was immersed in a watch-glass filled with mercury, and a similar glass 

 placed under the end of the longer leg, to receive the metal which 

 might pass over. At the end of twenty-four hours, a globule of mer- 

 cury was perceived at the lower end ; and in the course of five or 

 six days, all the mercury passed over, leaving a crop of beautiful ar- 

 borescent crystals, of an amalgam of lead, in the upper glass. 



The mercury did not pass along the surface of the wire, since the 

 lead exhibited, externally, but little change of appearance ; although 

 the progress of the penetration could be traced by a slight variation 

 of the colour of the oxide on the surface. 



The action is much influenced by the texture of the lead. When 

 a rod of cast lead, of the same size and form, was substituted for the 

 one before described, the globule of mercury did not make its ap- 

 pearance at the lower end until about forty days ; and all the mer- 

 cury of the upper glass had not yet (after three months) entirely dis- 

 appeared. 



The penetration takes place much more readily in the direction of 

 the laminae of the metal than across them A plate of thick sheet 

 lead was formed into a cup, and mercury poured into this ; and it was 

 found that before a drop had passed directly through, the mercury 

 oozed out all around the edge of the plate. 



Professor Henry stated that he had in progress a variety of ex- 

 periments to investigate this action; and if any results of import- 

 ance were obtained he would communicate them to the Society. 



Dr. Hare made a verbal communication to the Society, by 

 which it appears that he has obtained brilliant metallic spangles 

 of calcium. 



His processes have been the deflagration of the phosphuret of cal- 

 cium in an atmosphere of hydrogen ; the exposure of the anhydrous 

 iodide of calcium to a current of hydrogen,* or ammonia in an incan- 



* By a deflagrator of one hundred pairs of plates, fourteen inches long by 

 eight broad. 



