PEErACE. 
V 
there communicated intelligence to me, I should have had the op- 
portunity of directing operations, although at a distance, and without 
visiting the spot, — ^just as, through Mr. Elliot's kind and early in- 
formation, I was enabled to suggest the best manner of examining 
the Heathery Burn Cave, and of collecting any relics that might be 
met with in it. Of the mammoth bones at Leicester Mr. Drake 
kindly gave me immediate information. Of many other similar dis- 
coveries and occurrences I have also had early notice ; but my great 
desire is to get still more, — indeed, as much as possible, — of sucli 
knowledge. Every one who knows me will know that if the senders 
wish the information given not to be used, they have only to tell me 
so, and their desires will be properly respected. The value of re- 
porting events to some special geologist, is very great, and there can 
be no better course than to supply such intelligence to the Editor of 
this Magazine, which is intended especially to record the events of 
the passing time. I am also pleased to have these pages made use 
of, as has been done by Dr. Falconer in the concluding number of 
this volume, as a medium of making known requirements of particu- 
lar material for valuable labours in progress. 
I am also gratified at the free criticism of my own articles, espe- 
cially when the criticisms are as valuable as those of Mr. Scrope on 
my earthquake paper. In the speculations I have made, and in 
those I shall hereafter make, I am not actuated by any desire of in- 
novation, but wish rather to develop discussions of many points 
accepted as theories, often only because they are familiar doctrines, 
and as often on too slight grounds. 
In concluding this Preface to my sixth volume, I have only again 
to express my continued good wishes to my many friends. 
S. J. MACKIE. 
