502 EXPERIMENT STATION RECOED. 



The use of spectrophotometry in analysis, C. Fery and E. Tassillt (Ann. 

 Falsi/., 6 {1913), No. 52, pp. 73-78). — The use of an apparatus combining the 

 principles of the colorimeter and spectroscope for measuring the amount of 

 substance yielding a color is recommended in place of the usual colorimeter, 

 which involves many errors. The estimation of iron in water and copper in 

 foods is considered in this regard. 



Estimation of alkalis in rocks, H. V. Krishnayya (Chem. Neios, 107 (1913), 

 No. 2779, pp. 100, 101; ahs. in Jour. Chem. 8oc. [London], 104 (1913), No. 606, 

 II, p. 339). — The method consists in heating a suitable quautity of the powdered 

 rock in a platinum dish with hydrofluoric and sulphuric acids, and after re- 

 moving the excess of acid, dissolving the residue in boiling dilute hydrochloric 

 acid. If any material remains, the treatment with sulphuric and hydrofluoric 

 acids is repeated. The filtrate obtained is made up to a definite volume " and 

 an aliquot part, representing 1 gm. of the sample, is withdrawn. After evapo- 

 rating to dryness and igniting the residue, thus rendering the iron and alumina 

 insoluble, the alkali sulphates are extracted with boiling water, and without 

 filtering converted into chlorids by adding barium chlorid solution; some 

 barium hydroxid is also added. After removing the excess of barium with 

 ammonium carbonate, the alkali chlorids are weighed jointly as usual. The 

 potassium is then estimated as platinichlorid in the ordinary manner." 



Examination and judgment of water for agricultural and industrial 

 purposes (Ztsclir. Landio. Versuchsw. Osterr., 15 (1912), No. 11, pp. 1221- 

 1231). — This deals primarily with the criterions for judging water for agricul- 

 tural puri)oses. i. e.. drinking water for animals, baking, and other domestic 

 purposes, in the dairy, and for watering plants, but also includes the judgment 

 of water for starch manufacture, sugar refining, malting, brewing, alcohol and 

 yeast production, tanning, glue and gelatin manufacture, and silk spinning, 

 and a short chapter on the chemical and biological analysis of water. The 

 methods set forth were adopted by the officials of the Association of Austrian 

 Agricultural Experiment Stations. 



Examination and judgment of waste waters (Ztschr. Landw. Versuchstc. 

 Ostcn:, 15 (1912), No. 11, pp. 1232-1237).— These are the methods adopted by 

 the Association of Austrian Agricultural Experiment Stations in regard to the 

 examination of sewage water, especially from the standpoint of stream pollu- 

 tion, etc. 



The use of potassium palmitate in water analysis, C. Blacker, P. Grun- 

 BERG. and M. Kissa' (Chem. Ztg.. 37 (1913), No. 6, pp. 56-5S).— Potassium 

 palmitate is preferred to potassium stearate for use in Clark's and similar 

 methods for determining the hardness of water. The presence of humates 

 in boiler water does not interfere with the results obtained by the palmitate 

 method, but when soap is used the results are unreliable. In the analysis of 

 waters containing humates the indicator methyl orange can not be employed. 

 When comparing phenol phthalein with anthranilic acidazodimethylanllin it 

 was found that the neutral points were very near one another, and it is pro- 

 posed to use the latter comiwund as an indicator in place of methyl orange for 

 the determination of the temporary hardness which has been termed the 

 methyl orange alkalinity. It can also be employed in connection with deter- 

 mining the permanent hardness of water. 



Potassium palmitate solution may also be employed for determining the sul- 

 phates in water. For estimating the magnesium in water a modification of 

 the Pfeifer method is employed which is described. 



Estimation of total nitrogen. E. R. Noyks (U. 8. Naval Med. Bui., 7 (1913), 

 No. 3, pp. 394, 395).— The method, while primarily intended for the analysis of 

 urine, i.s considered of value for other purposes. It is carried out as follows: 



