Burette

BURETTE (from the French burette - jug), a graduated glass tube used for the precise measurement of liquid volumes.

Figure 1.

liquids (or gases in the case of a gas burette). For discharging the liquid, the burette is equipped at the bottom with a stopcock or a rubber tube with a clamp. It is very convenient to use a rubber tube with a glass bead or a short rod inserted in the middle of it. By pressing on the rubber with your fingers from both sides above the bead, a narrow slit is formed through which the liquid flows. Rubber closures are unsuitable when working with permanganate and iodine solutions, which destroy the rubber and decompose themselves. Stopcocks are inconvenient with alkaline solutions, which damage the ground joints and cause the stopcock to stick. To avoid errors associated with improper positioning of the eyes when reading the liquid level in a burette, it is convenient to use a burette with a colored stripe on the back (Shellbach burette), reading not by the edge of the meniscus, as is usually done, but by the point of the stripe (see figure 1). With frequent use of a solution, the burette is usually connected directly to a bottle (see figures 2 and 3), and there are a number of devices that ensure the automatic setting of the liquid level to zero (see figures 4 and 5). For measuring very small quantities of solutions, microburettes are used, with divisions down to hundredths of a cubic centimeter. Such microburettes are easily made from ordinary bacteriological pipettes by equipping them with a rubber closure (with a bead). Figure 6 shows such a burette connected to a bottle for the solution.

V. Engelhardt. BUREAU, ALL-UNION OF FOREIGN SANITARY INFORMATION, established in accordance with the decree of the Council of People's Commissars of the USSR of July 1, 1927, is an all-Union body attached to the People's Commissariat of Health of the RSFSR; it carries out all types of official sanitary and scientific communication with foreign countries in the field of public health. Its duties include: compiling, processing, and publishing information on the sanitary condition of the Union based on materials received from the People's Commissariats of Health of the union republics; liaising with the International Office of Public Hygiene regarding the course of epidemic diseases, the state of public health, and sanitary legislation in the Union, as well as exchanging periodic information on the sanitary condition of the Union with those states with which agreements have been concluded to this effect. The All-Union Bureau of Foreign Sanitary Information oversees the implementation of measures arising from the Regulation on the Sanitary Protection of the Borders of the USSR (Collection of Laws, 1926, no. 69, art. 532) and coordinates its activities with the People's Commissariat for Foreign Affairs. The Bureau includes one representative from the People's Commissariats of Health of all the union republics. The Bureau carries out its communication with foreign countries on scientific, medical, and sanitary issues (scientific congresses, conferences, exhibitions, "scientists' weeks," etc.) through representatives in Germany, France, and America. All issues related to business trips abroad along the health care lines (scientific, administrative assignments) are also resolved by the Bureau, which thus constitutes the body regulating personal scientific communication with foreign countries. With the help of its representative offices, the Bureau informs the public circles of the respective countries about the achievements of Soviet medicine and promotes mutual scientific exchange between the USSR and foreign countries ("Russian-German Medical Journal," etc.).