VOL.4, No. 7
A Cmm LABORATORY SODIUM PRESS
919
pieces should be cut as large as possible, a square piece may be rounded with a wood mallet. After the cylinder is filled, as quickly as possible screw the cap on tightly for this end of the cylinder. The press is now ready for operation which is accomplished by screwing in the piston, and the sodium wire will exude through the small hole in the other end. If measurements are correct the cylinder will he empty when the Thandle comes against the cap into which the piston rod screws. To refill, unscrew the piston rod until nearly out, push back the piston block and fill as before. This press has been satisfactorily used in this laboratory for several years.
UNITED STATES CIVIL-SERVICE EXAMINATION The United States Civil-Service Commission announces thc following open tompctitive examination for Associate Physical Chemist. Applications for associate physical chemist must be on file with the Civil-Service Commission a t Washington, D. C., not later than August 9th. The examination is t o fill vacancies in the Bureau of Chemistry and Soils, Department of Agriculture, and in positions requiring similar qualifications. The entrance salary in the Departmental Service a t Washington, D. C., is $3000 a year. A probationary period of six months is required; advancement after that depends upon individual efficiency, increased usefulness, and the occurrence of vacancies in higher positions. For appointment to the Field Service the salary will be approximately the same. The duties in the Bureau of Chemistry and Soils will he t o conduct research studies and technical investigations pertaining to fires in farm products, with special attention t o spontaneous comhustion and deterioration of hay, grain, cattle feeds, and other agricultural products, and the development of methods for their control and prevention. Competitors will not be required t o report for examination a t any place, but will be rated on their education, training, and experience; and a publication or thesis to he filed with the application. Full information may he obtained from the United States Civil-Service Commission, Washington, D. C., or the secretary of the hoard of United States civil-service examiners a t the post-office or customhouse in any city.
