1890.] MICROSCOPICAL JOURNAL. 65 



A New Method of Detecting Oleo in Butter. 



By Dr. THOMAS TAYLOR, 



MICROSCROPIST OF THE UNITED STATES DEPARTMENT OF AGRICULTURE. 



Dr. Thomas Taylor proposes the following new method of detecting 

 oleo in butter as a result of over i,ooo experiments : 



Dissolve in 20 c.c. of petroleum benzine, 140 grains of a mixture of 

 oleo and butter. Heat slightly to secure a perfect solution of the oleo 

 fat. Butter-caseine and animal tissues may be removed by passing the 

 liquid, while warm, through fine muslin. Fill a test-tube with the 

 solution and place in Ice-water. In about 20 minutes the oleo fat will 

 separate from the butter-fat and falls to the bottom of the tube, being 

 insoluble in cold benzine, while the butter-fat will remain in solution 

 in the benzine. Separate the oleo fat from the liquid butter-fat by fil- 

 tration. The fat recovered may be solidified by mechanical pressure, 

 placing it between several layers of bibulous paper to absorb the re- 

 maining^ benzine, after which the sheet of solid oleo mav be removed 

 from the paper with a palette-knife. The butter may be recovered by 

 evaporating the benzine by means of a sand-bath. 



A New Method for Detecting Cottonseed Oil in Lard. 



By Dr. THOMAS TAYLOR, 



MICROSCOPIST OF THE UNITED STATES DEPARTMENT OF AGRICULTURE. 



Dissolve in 20 c.c. of petroleum benzine, 140 grains of a mixture of 

 lard and cottonseed oil. Heat slightly to secure a perfect solution of 

 the lard. Animal tissues should be carefully removed by passing the 

 liquid while warm through fine muslin. Fill a test-tube with the 

 solution and place in ice- water. In about 20 minutes the lard falls to 

 the bottom of the tube by reason of its insolubility in cold benzine, 

 while the cottonseed oil remains in solution in the benzine. vSeparate 

 the lard from the cottonseed oil by filtration through fine bibulous pa- 

 per, and subject the recovered fat to mechanical pressure between sev- 

 eral folds of filtering paper, by which means the remaining benzine is 

 absorbed. The solidified fat may be removed from the paper with a 

 palette-knife. The cottonseed oil is separated from the benzine by 

 means of a sand-bath, which evaporates the benzine. 



Cleaning Diatoms from Sand. 



By NORMAN N. MASON, 



NEW YORK, N. Y. 



After removal of the organic matter with acid by the usual methods, 

 add to the diatoms and sand in a large bottle, thirty, forty, or fifty times 

 the quantity by measure of water, and gently shake until they are mixed. 

 This water, with the diatoms and sand kept suspended by an occasional 

 shake, is slowly poured in a small stream upon the upper end of a strip 

 of clean glass 3 feet long by 3 inches wide and securely supported. 

 The upper end of the glass should be from ^ to J inch higher than the 

 lower end, and the glass should be level transversely. Beneath the 

 lower end place any convenient receiver. The water and diatoms will 



