ABSTRACT
IN dealing with such a vast subject as this, on which solid books of no mean size, like that of Colonel Picard, have been written, I feel that it is very hard to avoid a slip into one of two opposite dangers. If one keeps to general outlines and obvious comment, one risks the charge of being dull and having nothing new to say. If one attempts to go into illustrative detail, and to touch on controversies, there is considerable chance that one may become unintelligible, from citing too many obscure facts. It may be a case of the wood that was invisible because there were so many trees. This second peril is the worse one; it is better to be obvious than to be obscure. There is much profit, after all, in endeavouring to formulate general conclusions.
