Unsigned American paintings have invited expertise from many art historians. As a rule, their research concentrates on biographical compendia with occasional enhancement from family and institutional records. Only a few art scholars, such as the late Lloyd Goodrich, troubled to note and tried to identify markings found on the painting's component parts. Just as today no item purchased is apt to be without its “made in….” label or stamp, so in the 19th-century the majority of artists' suppliers advertised themselves on the reverse of canvasses and on the strips of the wooden auxiliary supports.

In themselves distinctive forms, these marks of sellers often included location of the firm, and many firms moved about. Alexander Katlan's Directory is a treasure house of helpful information which was almost lost forever. The city address books studied were in tatters 50 years ago; by now those that remain must be secured in “rare book” sections of our libraries. The information assembled relates almost entirely to firms no longer in existence. As Katlan warns his readers (and invites corrections), data copied from 19th-century directories and institutional records are no more likely to be devoid of errors and omissions than are our own counterparts, gallery checklists, and telephone books. Nevertheless, the wealth of material, so painstakingly gathered, catalogued, and indexed can serve as a rare additional contribution in determining time and place of origin for unidentified American paintings.

Invaluable are the illustrations of variations in canvas stamps, wherever feasible catalogued and indexed in full text. As we find them, stencils are mostly abraded by time, labels survive in tantalizingly destroyed states, and canvas stamps uncovered beneath old adhesives during relining processes are usually illegible. Now, most if not all of these residues may be identified to their complete detail by comparison of the sorry vagueries with original photographs in Katlan's collection.

While no one may be positive how soon after purchase an artist made use of his materials, paintings cannot be dated EARLIER than the year in which a firm was located at an address stamped on its canvas reverse. Such evidence has been viewed as irrefutable in several matters of authentication and with the listings in this book, will act to prevent arguments of similar nature in the future. We have needed this Directory for years. It will be welcomed by libraries, art scholars, and conservators, welcomed by everyone who has serious concern with American paintings.