with their sugar content unchanged. [Illustration: FIGURE 3. RASP FOR SUGAR BEETS.] Such a machine is also useful in preparing vegetable matter for the separation of its juices in presses. Samples of sugar cane, sugar beets, apples and other bodies of like nature can thus be prepared to secure their juices for chemical examination. Such an apparatus we have found is fully as useful and indispensable in an agricultural laboratory as a drug mill for air-dried materials. It is often desirable in the preparation of roots for sugar analysis to secure them in a completely disintegrated state, that is with the cellular tissues practically all broken. Such a pulped material can be treated with water and the sugar juices it contains thus at once distributed to all parts of the liquid mass. The operation is known as instantaneous diffusion. The pulp of the vegetable matter is thus introduced into the measuring flask along with the juices and the content of sugar can be easily determined. Several forms of apparatus have been devised for this purpose, one of which is shown in fig. 3. This process, originally devised by Pellet, has come into quite general use in the determination of the sugar content of beets.[1] It is observed that it can be applied to other tubers, such as the turnip, potato, artichoke, etc. It is desirable, therefore, that an agricultural laboratory be equipped with at least three kinds of grinding machines; _viz._, first, the common drug mill used for grinding seeds, air-dried fodders, and the like; second, a pulping machine like the system of staggered saws above described for the purpose of reducing green vegetable matter to a fine state of subdivision, or one like the pellet rasp for tubers; third, a mill for general use such as is employed for making sausages from soft animal tissues. [Illustration: FIGURE 4. DREEF GRINDING APPARATUS.]