On the morning of November 3, 1820, William Wood posted on the bulletin-board of the "Commercial Advertiser" the following Notice to Merchants' Clerics and Apprentices. Those young gentlemen who are disposed to form a Mercantile Library and evening reading-room, are desired to attend a meeting for that purpose, at the Tontine Coffee House, on Thursday evening next at seven o'clock, when a plan of a Library and Association will be presented for their consideration. The young men of South Street, Front, Water, Pearl, Maiden Lane, and Broadway are particularly desired to attend.

This meeting was held on Thursday, November 9, 1820, and thus was started the Mercantile Library Association. On November 27 a constitution was adopted, and Lucius Bull was elected the first president. By the constitution the control of the library was placed in the hands of merchants' clerks ; they alone were permitted to vote and hold office. This provision has been continued up to the present time. While all persons of good character may become members of the library, merchants' clerks only have a voice in the management. The library was opened on February 12, 1821, at 49 Fulton street, with 150 members. The library quarters consisted of one room, and the opening found the association in the possession of about 700 volumes, most of which had been presented. At the end of the first year the books had increased to 1000 volumes, and the membership to 175. In 1826 the library had 6000 volumes, and was removed to more spacious quarters in the building of Harper & Bros., in Cliff street. In the year 1827 the association gave a course of ten lectures on Commercial Law; Seth P. Staples was selected as the lecturer. The success of these lectures induced the management to establish a lecture department, and from this time up to the year 1875, every winter, a course of from ten to twelve lectures was delivered under the library auspices. In 1828 the signs of public favor were such that the idea was conceived of soliciting subscriptions to erect a building for the rapidly accumulating library, and wherein the lectures could be given, and other educational efforts successfully carried out. A meeting of citizens was called, and met in the library room in Cliff street. A separate organization was effected among the merchants for the purpose of building and holding a suitable structure for the use of the Mercantile Library. This organization was named the Clinton Hall Association. In the course of the year $33,500 was raised. The new building was erected on the corner of Nassau and Beekman streets (now the site of Temple Court and the Nassau Bank), and was dedicated, under the name of Clinton Hall, on November 2, 1830. The cost of building and land was about $55,000.

The Clinton Hall Association acts as trustees for the library, and all surplus revenues derived from this estate go to the library for the purchase of books, etc. The money for the erection of the building was obtained by issuing stock at the par value of $100. The Clinton Hall stockholders are entitled to all the privileges of membership of the Mercantile Library. In 1838 a class department was organized, and for many years instruction was given in bookkeeping, drawing, mathematics, penmanship, and the various languages. For years the association was the possessor of four free scholarships two conferred by the University of New York and two by Columbia College. By these scholarships the library was enabled to be the means of educating many worthy young men who otherwise would not have been able to obtain the advantages bestowed. These scholarships continued until the University of New- York became free to all and Columbia College abolished all unendowed free scholarships.

Twenty years after the dedication of the building on the corner of twenty years after the dedication of the building on the corner of Beekman and Nassau streets, the library had outgrown the accommodation, and the site was considered too far down town by the migration of the people northward. Agitation for a new building further up town was now commenced. After a long and bitter contest between two factions, one favoring removal up town and the other opposing, the Astor Place Opera House (which had been the scene, in 1849 of the conflict between the friends of the rival actors Edwin Forrest and "William Charles Macready) was purchased. The cost of this building was $140,000. About $115,000 more was expended in adapting it for the purpose of the library. The association took possession and moved the books into the building in April, 1854. At this time the library possessed 43,000 volumes, and the capacity of the building' was estimated at 120,000 volumes.

After an occupancy of thirty-six years, and when the allotted room for books had for many years been crowded and every available spot utilized, and the development of the library greatly retarded for want of room, this building was vacated in April, 1890, in order that it might be demolished, and the new building which now occupies the site erected. For one year the library occupied temporary quarters at 67 Fifth Avenue, and returned to its new home in April, 1891. The first load of books was taken into the new building on the morning of April 16, 1891. This building is a fire-proof structure of buff brick and red sandstone, seven stories high. It has a frontage on three streets as follows, 159 feet on Eighth street, 149 feet on Astor Place, and 52 feet on Lafayette Place. The width of the building on the end overlooking Broadway is 98 feet. The library quarters are on the seventh floor, and are reached by two steam elevators. The circulating department for home use is on the seventh floor. On this floor are also the catalogue department, work-rooms, the directors' room, and the librarian's office. The apartment for the storage of books is considered one of the finest, if not the best, for its purpose in the country.

In addition to having light on all sides, it has a skylight occupying two thirds of the roof space. The height from the floor to the skylight is 25 feet. The full storage capacity is 475,000 volumes. At present it has a book-stack two tiers high, each tier being seven feet in height and so arranged that a third tier of seven can be added when required. This book-stack is fitted with adjustable shelves, the supports being the latest and most improved pattern. The bookcases are double, and the width from face to face is 18 inches. The distance between the cases is three feet. No book is beyond the reach of the attendant standing on the floor or on the gallery. The stairs and flooring of the stack are made of iron. In this room is also the principal card catalogue, a model of perfection and simplicity. The cards of this catalogue are contained in two cases of beautiful polished oak, each case having thirty-three drawers. The arrangement or plan is in three divisions. The first division contains the author and title cards arranged alphabetically in one alphabet. The second division consists of the subject entries arranged alphabetically by subjects and classes". The third division is entirely fiction, arranged under the name of the author and the title of the book in one alphabet. Here also may be found the printed catalogues, which can be consulted with ease and comfort sitting at tables arranged for this purpose, with order blanks on either end and within easy reach. On January 1, 1893, the total number of books in the library was 241,548.

On the sixth floor is the reading-room and the department for reference and study. This room is on the east end of the building, overlooking the square bounded by Lafayette Place, Fourth Avenue, Astor Place, and Eighth street. It is open to light and air on three sides. Its length is 64 feet, its width at one end 64 feet, and at the other 47 feet. This room has been arranged specially for the convenience and comfort of readers and students. The floor is covered with a cork carpet, rendering movement across it noiseless. It is furnished with arm-chairs made of oak and upholstered in leather. In the center of the room is a case with compartments for six hundred newspapers and magazines. Each one of these compartments has the name, in gold letters, of the periodical it contains. No hand-files of any kind are in use. The current numbers of periodicals only are kept in this case, but the back numbers are immediately behind the superintendent's desk, and can be had on application. At the back of the periodical-case are
shelves which contain the works of ready reference, such as the various encyclopedias, dictionaries, books of statistics, etc., for the free use of the members, without being compelled to write an order for them. The room has numerous tables of convenient size, made specially for the library. Students and readers wishing to order books for reference, can do so without leaving their chairs, as each table is furnished with compartment which contains blank orders. These tables also have drawers on either side, wherein is found writing-paper for use of members. Immediately in the rear of the reading-room is the storage-room for the books belonging to the reference department. The storage capacity of this room is for 140,000 volumes. At present it contains about 50,000 volumes, principally the documents of the National and State governments, and bound volumes of newspapers and magazines which are extremely valuable for reference. The library is lighted throughout with electricity.