these short lengths are generally threaded and drawn together at their ends, making, so to speak, little arches—­so that although on the under side of the material there is only a tiny thread, on the upper side there is a strong arch, practically of copper.  On boxes and other ornamental productions of this same period, pieces of purl are not infrequently found laid flat like little bricks; and houses, castles, etc., are often represented by means of it; but on books the general use is either for flowers, grounds, or (in very small pieces) to keep on spangles.  Obviously any coloured silk can be used in making this thread, so that it may be said that for coloured silk work, where strength is required, flowers worked in purl are the best.  The colours used when roses are represented are usually graduated,—­yellow or white in the centre, then gradually darkening outward, yellow, pale pink, and red, or pale yellow, pale blue, and dark blue.  Purl flowers are usually accessories to some regular design, but, in one instance at least, to be described later on, it supplies the entire decoration of a small satin book.

Bible, etc. London, 1642.

The design on a Bible with Psalms, printed in London in 1642, bound in fine canvas, and measuring 6 by 3-1/2 inches, is the same on both sides.  The ground is all laid, or couched, with silver threads, caught down at intervals by small white stitches.  In the centre is a circular silver boss, and out of this grow four lilies worked with silver thread in button-hole stitch; each of these lilies has a shape similar to its own underneath it, outlined with fine gold cord, and filled in with red silk; representing altogether white flowers with a red lining.  These four red and white lilies make together the form of a Maltese cross, and between each of the arms is a purl rose with yellow centre and graduated blue petals.  A double oval, with the upper and lower curves larger than the side ones, marked with a thick gold cord, encloses the central cross, and the remaining spaces are filled with ovals and lines of gold guimp, with here and there a little patch of red or yellow purl, the extremities of the upper and lower ovals being filled with threads of green silk loosely bound with a silver spiral, worked to represent a green plot.

[Illustration:  13—­Bible, etc.  London, 1642.]

The upper and lower curves of the oval are thickened by an arch of gold thread laid lengthwise, and kept in place by little radiating lines of red silk.  In each corner is a purl rose, with blue centre, the petals graduating in colour from pale yellow to dark red, with leaf forms and stalks of gold cord and guimp.  At the top and bottom of the oval is a many-coloured purl rose, and the spaces still left vacant are dotted with little pieces of red, blue, and yellow purl and spangles.  On the front edges are the remains of two red silk ties.

[Illustration:  14—­Bible.  London, 1648.]