Although the purpose of the dome arabesque is primarily to give an agreeable impression of light and shade, the individual figures of which it is composed are nearly as interesting a study as the general effect of the whole. The variety of the figures is almost bewildering--lions’ heads, sea-horses, dolphins, urns, cartouches, griffins, shells, storks, caryatides, tridents, eagles, cherubs, half-figures, geniuses--altogether something like forty-five principal type-designs, interwoven with very many smaller but no less beautiful pieces of ornament. All are adapted from Renaissance models of the best and purest period, and are combined with the utmost spirit and harmony in an arabesque whose every portion has equal artistic value. No single figure catches the eye; broad horizontal and vertical bands of decoration, gradually diminishing as they approach the top, encircle and ascend the dome, each with its particular “note” of arrangement and design, but all cunningly united to form an indisputable whole, everywhere balanced and restrained. [Illustration: DETAIL OF THE DOME.] It may be of interest to the visitor to learn that one of the most novel and ingenious pieces of engineering connected with the construction of the Library was a so-called “travelling” or rotary scaffold, devised by Mr. Green for the use of the workmen employed on the stucco decorations of the dome. It may be likened to a huge pair of steps, ascending from the upper entablature to the lantern. Its upper end thrust against an iron pintle secured to beams laid across the eye of the lantern, and was steadied at the bottom by a pair of flanged wheels, which travelled on a track in the entablature, so that the whole apparatus could be traversed entirely round the room. The various stages or landings were adjusted to fit the concave of the dome, with the result that the accuracy of the curve could be tested with almost mathematical exactness. At one time two of these scaffolds were swung to the same pintle. =Mr. Blashfield’s Paintings.=--The position of Mr. Blashfield’s decorations in the Collar and Lantern of the dome is the noblest and most inspiring in the Library. They are literally and obviously the crowning glory of the building, and put the final touch of completion on the whole decorative scheme of the interior. The visitor will see how, without them, not a painting in the building would seem to remain solidly and easily in its place, for they occupy not only the highest, but the exact central point of the Library, to which, in a sense, every other is merely relative. As was hinted in the description of Mr. Vedder’s paintings, Mr. Blashfield was almost necessarily drawn to select some such subject as he has here chosen--the Evolution of Civilization, the records of which it is the function of a great library to gather and preserve.