Ye maids who toiled so faithful at the mill
Now cease from work and from these toils be still;
Sleep now till dawn and let the birds with glee
Sing to the ruddy morn, on bush and tree;
For what your hands performed so long, so true,
Ceres[15] has charged the water-nymphs to do;
They come, the limpid sisters, to her call,
And on the wheel with dashing fury fall;
Impel the axle with a whirling sound
And make the massive millstone reel around
And bring the floury heap luxuriant to the ground.

Nothing can be simpler than the water-mill described above; it was the old mill of the upper and nether millstones, the old hand mill turned by water. That was all. Yet, as simple as it was, many centuries passed after its invention before a new principle in flour making was discovered. There were inventions for lowering and raising the stone so as to grind finer or coarser as might be desired, and there were improvements in the kind of water wheels employed, and better methods of sifting the flour from the bran were discovered from time to time, but the water-mill invented in the time of Julius Cæsar remained practically unchanged until the early part of the nineteenth century, when the last step in the development of the mill was taken.[16]

FIG. 13.—AN EARLY FLOUR ROLLER-MILL.

About 1810 millers in Austria, more particularly those in Vienna, began to grind their grain by passing it between two horizontal rollers (Fig. 13). The rollers were spirally grooved and turned toward each other. There was a wide difference between this process and the one to which the world was accustomed, yet the new method was found to be better than the old one. Austrian flour and Austrian bread became famous. The delicious Vienna bread on our tables of course has never seen Vienna. It is called "Vienna bread" because it is made out of a kind of flour which was first ground in the Austrian capital. The Austrian way of grinding grew rapidly into favor among millers everywhere. In the United States where there was so much wheat to be ground the roller process was taken up eagerly and improved upon as only Americans know how to improve upon an idea. In the flour mills of the West the grain was soon passing through a series of rollers. By the first pair of rollers the grain was simply cracked into pieces somewhat coarse. Then after being bolted (sifted) it was passed between a second pair of rollers and reduced to a greater fineness. Then it was bolted again and passed between a third pair of rollers. The rolling and sifting continued until a practically pure flour was obtained. A pure flour is the modern miller's ideal. He wants a branless flour and a flourless bran. The old stone mill could not grind this kind of flour. Before the roller mill appeared there was always bran in the flour and flour in the bran.

The invention of the flour roller-mill (Fig. 14) is the last step in the development of the mill. The roller process has almost entirely driven out all other processes. Now and then we see by the roadside an old fashioned mill with the upper and nether stone, but we seldom see one that is prosperous and thriving. Millers, like everybody else in these days, do business on a large scale and to make flour on a large scale they must use the roller-mill. Thus the hole in the rock in which a handful of grain was laboriously crushed has, through long ages of growth, become the great factory in which thousands of barrels of flour are made in a day.