MULL. ECONOMY. 



and forgets that he cannot combine the elegancies and 

 comforts of modern life, with a dark and disturbed re- 

 sidence in a rude and narrow tower. 



TOBERMORY (St. Mary's well) has no longer a chapel 

 to mark the site of its healing spring; which has dis- 

 appeared, like the Florida that lies off the shore buried 

 with many more of the Invincible Armada, deep beneath 

 the waves.* But Tobermory, if it offers nothing to 



* With respect to the Florida I find on record a very important 

 chemical fact, which, ten years ago, I had imagined to be my own 

 discovery. The Highlanders who anticipated me, have still longer 

 anticipated others who have recently noticed this circumstance in 

 the public journals. 



In 1740 Sir Archibald Grant and Captain Roe attempted, with 

 the assistance of divers, to weigh that ship. The attempt was un- 

 successful, but guns both of brass and of iron were brought up. The 

 former had the mark of an English founder, R. and J. Phillips 1584, 

 with a crown and E. R. The iron guns were deeply corroded, and 

 on scraping them became so hot that they could not be touched; 

 but they lost that property after two or three hours exposure to the air. 



I observed the same circumstance, first, in some iron work that 

 had long been immersed in the porter backs of a London brewery, 

 and then confirmed it by some direct experiments. It has since been 

 remarked in the waste pipes of a brewery at Plymouth Dock and 

 under other analogous circumstances, and the experiments have been 

 repeated by other chemists. The matter thus remaining after the 

 solution of the iron is plumbago, in no respect distinguishable from 

 that substance in its ordinary mineral state. There is nothing unex- 

 pected in this result, since carbon is known to be a constituent 

 of cast iron. To ascertain the state in which it exists- in the iron is- 

 however a matter of more importance and of more difficulty ; nor 

 does our knowledge at present afford any means of determining it by 

 direct analysis. The eye does not discover any difference between 

 the substance in question before and after this sort of combustion, 

 for which the presence of oxygen is, as in other cases requisite. 

 There is however little doubt that it is analogous to the combustion 

 of the inflammable metals, or of the alkaline bases. It is equally 

 probable that a portion of the change is effected during the solution 

 of the iron. In some cases indeed the plumbago is completely formed, 



