In this, like the first machine, the warp threads are wound upon a roller at the bottom of the machine, and are carried up to a work beam or roller situated at the bottom of the machine ; also the diagonal threads are wound upon small detached bobbins, and regularly interspersed between the win p threads ; but there is no farther similarity be tween the two machines. The bobbins are small flat wheels about the size and thickness of a shilling, with a deep groove in the edge to wind the thread upon. These bob bins are fitted into a small carriage or frame, in which it is at liberty to turn round when the thread is drawn of but there is a slight spring which makes as much resis tance as is necessary to draw the thread tight. The bob bins and their carriages are so thin, that, when placed side by side in rows, they will not occupy more room than the breadth of lace they are intended to make.
The longitudinal threads are stretched in a perpendicu lar direction from the thread roller to the lace roller, so as to form a row of parallel threads arranged at equal dis tances from each other; and, to guide them, each thread is conducted through a small eye in a wire resembling a needle. Two rows of such guides are fixed on two bars.
which are placed horizontally, and each bar is caps ble o moving a small space endways, and will then carry the threads sideways with them, which indeed is the object of these rows of guides.
On each side of the row of perpendicular threads is fixed an horizontal bar, called a comb-bar, the upper sur face of which is cut into notches or grooves for the recep tion of the small carriages which contain the bobbins. The grooves are in the upper sides of the bars, and crossways or perpendicular the length of the bar. The comb-bar at the back of the row of threads is exactly correspondent with that in front, and the intervals of the grooves in both are the same as the spaces between the rows of guides and threads. The carriages of the bobbins are placed in the grooves of the comb-bars, and slide freely therein, so as to be capable of passing out of the groove of one bar be tween the threads, and into the grooves of the opposite bar ; but the distance between the two comb-bars is such, that the bobbins will enter into the grooves of one bar before they quit the grooves of the other.
In working the machine, all the bobbins of the whole row are connected together by means of a thin bar or ruler, the edge of which is insetted in a notch made in the car riage of each bobbin, so that all the bobbins can be moved in the grooves of the comb-bar at the same time, and can be passed from one bar between the perpendicular threads, and be received into the other bar. At the opposite end of each carriage is a similar notch, for the reception of ano ther such ruler ; but only one is used at a time. By means of these two rulers, the bobbins can be transferred from one comb-bar to the other, and will be passed between the row of threads. Suppose, for instance, that all the bobbins are situated in the front comb-bar, the ruler, which is in its notches, being pushed backwards, will move all the bobbins at the same time through between the threads, and enters them into the grooves of the back comb-bar ; the other ruler is then applied, and when its edge is put into the notches at the back of the bobbins, the ruler in front is lifted up to take its edge out of the notches in front ; this being done, the bobbins are drawn completely through between the threads in the grooves into the back comb-bar.
The result, therefore, of this train of manipulations, is to transfer the bobbins from the front comb-bar to the back, and in so doing they are made to pass between the threads. This being done, the bar sustaining the guides is moved sideways through a distance equal to the interval between two adjacent grooves of the combs, and then the row of bobbins is returned from the back comb-bar between the perpendicular threads, and brought into the front comb bar by the same movements which have already been de scribed. Now it is evident that in the bobbins passing be tween the perpendicular threads the first time, those per pendicular.threads which were on the right side of each bobbin would be on the left side of the same bobbins when they return ; by which means each of the threads of the bobbins makes a turn round its corresponding perpendicu lar thread.
The action being repeated, each bobbin makes a com plete twist round its corresponding bobbin thread, and the sides of the meshes are thus formed ; but it is to be under stood, that every time after the bobbins have been passed between the perpendicular threads, before they are passed again in an opposite direction, the row of guides is to be moved a space, as before mentioned.
But before we can clearly explain the manner of cross ing the bobbin threads, we must point out a circumstance which we omitted in order to render the descrip lion less complicated, viz. that in order to obtain more room for the bobbins, they are arranged in two rows, one before the other, in the same grooves of the comb-bars ; and that one row is first passed between the perpendicu lar threads, and then the other. Also the rows of guides before mentioned, are two in number, and one half of the number of perpendicular threads, that is, every alternate thread, is conducted through the guides of one row, whilst the intermediate threads are conducted through the guides of the other row. In order to make room for the passage of the bobbins, the two rows of guides are so placed dur ing the time that the bobbins pass, that they collect the perpendicular threads one before the other, each alternate thread falling behind its neighbour, by which means only one half of the number of threads appear in front, and of course the spaces between them arc rendered double to what they would be, if the whole number of perpendicular threads were placed at regular distances. Alter one half of the number of bobbins, that is, one of the rows of bob bins, has passed between the threads, then, before the other row is passed, the rows of guides are so moved as to sepa rate those threads which were placed behind each other in the former instance, and arrange those threads behind each other which were separated in the former instance ; conse quently, when the remaining row of bobbins is passed, the whole number of bobbins will have passed between threads, as we have described ; but as this is effected at two opera tions, bobbins of a double thickness can be employed.