In the general style of their designs the Primitives were all controlled by one fundamental aim--that of decoration. This dominating quality appears most clearly in the large actor-prints which we associate with the names of Kwaigetsudō, Kiyonobu, Masanobu, and Toyonobu. To an extent greater than the artists of any succeeding period they eschewed minuteness of detail and accuracy of representation, sacrificing these things for the sake of achieving broad decorative effects combined with vigorous movement. A certain unique simplicity and grandeur in the spacial and linear conceptions of these men gives to the whole Primitive Period a Titanic character that distinguishes it. In the best works of this time the stylistic finish of the drawing is masterful. It translates motion into sweeping caligraphic lines, and creates imposing calm by the poise and balance of severe black-and-white masses. Just as in opera the flow of music induces in the auditor a state of semi-trance that makes him oblivious to the patent absurdities and unrealities of the action, so in these pictures the rhythmic flow of the composition lifts the consciousness of the spectator to a plane where it ceases to take note of the incorrect report of Nature and loses itself in the enjoyment of the noble decorative conceptions that actuate the creating hand. A profound formalism dominates these works. The figures are purely one-dimensional; the picture is a flat pattern of lights and darks bounded by the sharp outline of great curves. In the actor-pieces no real portraiture of the actor as an individual is essayed; the artist's aim is rather to convey some sense of the dynamic power of the rôle in which the actor appears. He succeeds so well that his pictures, though not representations of individuals, stand as abstract symbols of grace or of power. Historically, one of the chief interests in this period centres upon the notable developments in technique. Wood-engraving was, as we have seen, already known when the period opened; but it had not yet been subjected to the purposes of the artist. Confined almost exclusively to crude book illustrations, it had as little artistic significance as the cheap hand-painted sketches called _otsu-ye_, which, produced by hundreds, were sold for the amusement of the populace. With the advent of the gifted Moronobu, the book-illustration was transformed into an important and beautiful creation. Going further, Moronobu and his successors produced single-sheet prints of large size, in black and white only, that served all the purposes of paintings and were capable of being reproduced without limit. These black-and-white prints were called _sumi-ye_ (Plate 1). Books and albums by him appeared at various earlier dates, but the first of his single-sheet prints was issued about 1670.