348 



SCIENCE 



[N. S. Vol. XXXIII. No. 844 



only be strontium. If barium is present, it should 

 first be removed with chromate ion. 



3. If barium and strontium are absent, pre- 

 cipitate calcium with the sulfite without acid. 



4. If strontium and calcium are present to- 

 gether, there are two methods of procedure: 



(a) Add to a portion of the solution sodium 

 sulfite and warm gently, not above 30°, shake 

 well and filter. The calcium is almost completely 

 precipitated while much of the strontium remains 

 in solution. Boil a portion of the filtrate. The 

 remaining strontium separates. If strontium is 

 absent there is no precipitate or at least a faint 

 cloud. Pour over the precipitate on the filter a 

 very dilute solution of acetic acid and to the 

 filtrate add ammonium oxalate. A precipitate is 

 calcium oxalate. 



(6) Make the solution acid with acetic acid, 

 add sodium sulfite and boil. Be sure that acid 

 is added in excess of that required to neutralize 

 the sulfite solution which is alkalin by hy- 

 drolysis. The mixture should be but slightly acid. 

 Shake well. Let stand a few minutes to settle, 

 then filter, pouring the liquid through repeatedly 

 until it is clear. Dilute a portion of the filtrate 

 with an equal quantity of water and add am- 

 monium oxalate. A precipitate is calcium oxalate. 



DIVISION" OF PHYSICAL ANB INORGANIC CHEMISTBT 



Electrical Equipment for Electroanalysis and 

 Electric Furnace Work: Feancis C. Fbaey. 

 The author described specially designed switch- 

 boards for the distribution of the current from a 

 storage-battery to a class in electroanalysis, and 

 for the use of the individual students in the class. 

 The boards are designed from the view-point of 

 maximum efficiency and flexibility at minimum 

 expense. 



The arrangement of a 10-K.V.A. transformer 

 for work in the furnace-room was described and 

 illustrated. Four secondary coils are provided, 

 two giving 10 volts and two 20. By means of 

 copper straps these may be connected in all pos- 

 sible useful combinations. Five and 10 per cent, 

 taps on the high-tension (220-volt) side of the 

 transformer allow the increase or decrease of the 

 voltage thus generated by 5 or 10 per cent., thus 

 giving four possible voltages for each combination 

 of the secondary coils. Suitable circuit-breakers 

 are provided on both the primary and secondary 

 sides of the transformer. Suitable measuring in- 

 struments are provided, and a large double-throw 

 double-pole switch allows the bus bars in the 

 furnace-room to be connected to either direct or 

 alternatins current. 



Abstracts for the following papers have not 

 been received: 



"Electric Osmose," Harry N. Holmes. 



" The Effect of Continued Grinding on Water 

 of Crystallization," Nicholas Knight. 



" The Determination of Manganese by the So- 

 dium Bismuthate Method," M. H. P. Brinton. 



" The Sulfur Hydrosol Prepared by a New 

 Method," Harrison Everett Ashley. 



" The Dielectric Capacity of some Liquid Hy- 

 drides," R. C. Palmer and Herman Schlundt. 



"A Case of Ammonia Deliquescence," W. P. 

 Bradley. 



" The Action of Ammonia upon Ammonium 

 Sulfocyanide," W. P. Bradley. 



" On the Electrochemical Oxidation of Hydra- 

 zine," J. W. Turrentine and Willis A. Gibbons. 



" Contribution to the Electrochemistry of Hy- 

 dronitric Acid: the Electrochemical Corrosion of 

 some Metals in Sodium Trinitride Solution," J. 

 W. Turrentine, 



" Experiments on the Reliability of the Borax 

 Bead Test for Varying Mixtures of Nickel and 

 Cobalt," P. Rothberg and L. J. Curtman. 



" A Study of the Factors Influencing the Sys- 

 tematic Qualitative Determination of Barium," 

 E. Frankel and L. J. Curtman. 



" Rapid Electrolytic Deposition of Metals from 

 Boiling Solutions," Franz F. Exner. 



" The Pocket Spectroscope — A Neglected NeC3S- 

 sity for the Practical Chemist," Chas. S. Palmer. 



" Physical Properties of Aqueous Solutions con- 

 taining Ammonia and Citric Acid," Robert A. 

 Hall and James M. Bell. 



" The Action of Hydrogen Sulfide on certain 

 Metallic Salts in Non-aqueous Solvents," W. G. 

 Wilcox. 



" The Heat of Neutralization of Pyridine in 

 Various Solvents," J. Howard Mathews. 



" The Use of a Dewar Flask in Measurements 

 of Heats of Neutralization," J. Howard Mathews 

 and A. F. 0. Germann. 



" Surface Tension Measurements at the Surface 

 between two Liquids," W. D. Harkins. 



" Equilibrium in the System Lead Nitrate Pyri- 

 dine," J. H. Walton, Jr., and R. C. Judd. 



" The Action of Oxides of Lead on Normal 

 Potassium Tartrate," F. C. Krauskopf, 



" On the Interaction of Metallic Sodium and 

 Mercury," L, Kahlenberg and David Klein, 



" The Vapor Pressure of Dried Calomel," Alex- 

 ander Smith and A, W. C, Menzies, 



" The Vapor Pressures of Sulfur," Allan W, C, 

 Slenzies. 



