I wish to refer specially to the grateful acknowledgment that is due Arthur Keith's _Geology of the Catoctin Belt_ and Carter's and Lyman's _Soil Survey of the Leesburg Area_, two Government publications, published respectively by the United States Geological Survey and Department of Agriculture, and containing a fund of useful information relating to the geology, soils, and geography of about two-thirds of the area of Loudoun. Of course these works have been the sources to which I have chiefly repaired for information relating to the two first-named subjects. Without them the cost of this publication would have been considerably augmented. As it is I have been spared the expense and labor that would have attended an enforced personal investigation of the County's soils and geology. And now a tardy and, perhaps, needless word or two in revealment of the purpose of this volume. To rescue a valuable miscellany of facts and occurrences from an impending oblivion; to gather and fix certain ephemeral incidents before they had passed out of remembrance; to render some account of the County's vast resources and capabilities; to trace its geography and analyze its soils and geology; to follow the tortuous windings of its numerous streams; to chronicle the multitudinous deeds of sacrifice and daring performed by her citizens and soldiery--such has been the purpose of this work, such its object and design. But the idea as originally evolved contemplated only a chronology of events from the establishment of the County to the present day. Not until the work was well under way was the matter appearing under the several descriptive heads supplemented. From start to finish this self-appointed task has been prosecuted with conscientious zeal and persistency of purpose, although with frequent interruptions, and more often than not amid circumstances least favorable to literary composition. At the same time my hands have been filled with laborious avocations of another kind. What the philosopher Johnson said of his great _Dictionary_ and himself could as well be said of this humble volume and its author: "In this work, when it shall be found that much is omitted, let it not be forgotten that much likewise is performed; and though no book was ever spared out of tenderness to the author, and the world is little solicitous to know whence proceeded the faults of that which it condemns; yet it may gratify curiosity to inform it, that the _English Dictionary_ was written with little assistance of the learned, and without any patronage of the great; not in the soft obscurities of retirement, or under the shelter of academick bowers, but amidst inconvenience and distraction, in sickness and in sorrow."