INTRODUCTION.

XV

threw them in my way. I was furnished by several

individuals with documents and illustrations, of most of which I was permitted the free use, while at others it was necessary to glance only. Some I have been compelled, after mature consideration, wholly to suppress, lest persons to whom I consider myself deeply indebted should be compromised by their publication. But these are few; the greater number I have introduced, or employed as the ground-work of my statements, and their authors are entitled to my gratitude; though to express it in any other than a general way might be injurious to their interests or their safety.