xxiv. Proceedings. [May 18th, 1920. 



Ordinary Meeting, May iSth, 1920. 

 Mr. R. L. Taylor, F.C.S., F.I.C {Vice-President), in the Chair. 



A vote of thanks was passed to the donors of the books upon 

 the table. 



Dr. R. S. Willows, M.A., exhibited and described a lantern 

 slide giving a transverse section of cotton fibre, magnified 

 20,000 times, showing Ball's daily growth rings. 



Mr. William Thomson, F.R.S.E., F.CS., F.I.C, read the 

 following paper by himself and Mr. Herbert S. Newman, 

 M.Sc.Tech., containing further notes on their communication 

 read before the Society on February 3rd, 1920. 



" On the Behaviour of Amalgamated Aluminium and 

 Aluminium Wire." 



When aluminium wire (that used by us was 15 /i oooth of an 

 inch in diameter) is brought into contact with mercury there at 

 once begins to grow from the wire a fine feathery 7 substance 

 which may extend in an hour or two to as much as half an inch 

 or more ; this substance is hydrated aluminium oxide (alumina) 

 associated with a small quantity of mercury in the free state. 



This observation has been made frequently by others ; 

 although we find scanty record of it, and none in the indices of 

 the Scientific Journals to which we had access. Carl Jehn and 

 H. Hinze (Ber., 7, 1498), on the nth November, 1874, refer, in 

 a note of a few lines, to aluminium as combining with mercury 

 and forming these curious growths. According to them, after 

 the piece of aluminium had been rubbed with wash leather 

 which had been in contact with mercury, the rubbed surface 

 became warm and dull; and almost instantaneously white tufts 

 began to grow from it to a final length of 3 cm. " These proved 

 to be A1 2 3 ." 



A reference is made to it in No. 15 of " The Model Engineer 

 Series,'' Third Edition, page 56, which is a work written to 

 provide " Scientific Amusement." In this the author, Aurel de 

 Ratti, says this phenomenon was discovered by him accidentally 

 in 1895. The aluminium he used was obtained by breaking off 

 a piece from an aluminium pen-holder, in order to obtain a 

 clean and rugged edge without which the experiment would not 

 succeed. He thoroughly moistened the piece and then dipped 

 it into mercury : in a minute or two afterwards small white 

 spots appeared on the sharpest corners and these rapidly grew 

 till they appeared like feathery growths about an inch long. 



In his work entitled "The Evolution of Matter," Third 

 English Edition (1907), p. 405, Dr. Gustave Le Bon speaks of 

 " The Transformation of the properties of Aluminium " by its 



