[Proc. Roy. Soc. Victoria, 28 (N.S.), Part I., 1915]. 



Akt. VII. — An Occurrence of Ammonium Chloride at 

 Frankston. 



By E. J. HARTUNG and A. C. D. RTVETT. 



[Read July 8th, 1915). 



In the immediate neighbourhood of the Sports Ova) at Franksto?i 

 there was, until some two years ago, a small, shallow lake, with an 

 island about forty yards in diameter in the centre. The lake has 

 gradually drained, and, except after heavy rain, a dry, firm annular 

 bed of earthy material surrounds the one-time island. The island 

 and the banks consist of accumulations of decaying wood, roots, and 

 leaves, together with much siliceous earth (see analytical results 

 below). The living vegetation consists of Acacia, Melaleuca, rushes, 

 etc. 



About the middle of March, 1915, a fire was started by some boys 

 in the ti-tree scrub on the banks and island. Apparently the 

 fire was soon extinguished on the surface, but it has since spread 

 underground, and has defied the efforts of local municipal officers 

 to put it out. The authors visited the place on May 15, and again 

 some ten days later. During these ten days heavy rain had fallen, 

 without greatly affecting the fire. The combustion was still active 

 and the diameter of the unburnt central portion of the island had 

 decreased by some six or eight yards. No flames were to be seen, but 

 white smoke issued from a number of vents in the ground. This 

 smoke had a very specific smell, and on the Avails of the fissures and 

 in the openings whence it escaped, there were deposited very bea\i- 

 tiful incrustations of ammonium chloride crystals, in cubes and inter- 

 lacing needles. The white colour of the smoke and its specific smell 

 were doubtless due almost solely to fumes of this salt. As the fire 

 spread, the surface vegetation was killed at the roots, and fell down. 

 It was unsafe to walk over the burning areas without the support of 

 branches of scrub. 



The ash left was, for the most part, very voluminous, and varied 

 in colour from dirty white, through pink and red, to brownish 

 purple. In parts the ash was more compact. The bed of com- 

 bustible matter was apparently several feet deep. 



Analytical Work. 



One might reasonably suspect that in the course of slow combus- 

 tion, the nitrogenous constituents of the decaying plant material 



