Foods: their composition and analysis : A manual for the use of analytical chemists and others. With an introductory essay on the history of adulteration / By Alexander Wynter Blyth. With numerous tables and illustrations.

  • Alexander Wynter Blyth
Date:
1882
Catalogue details

Licence: Public Domain Mark

Credit: Foods: their composition and analysis : A manual for the use of analytical chemists and others. With an introductory essay on the history of adulteration / By Alexander Wynter Blyth. With numerous tables and illustrations. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

    600/673 page 555
    is then reduced to the proper strength by proof spirit. If work- ing in cc. and grms. it should be of such a strength that 14-25 cc. arerequii-ed to form a pei-manent lather with 50 cc. of the calcic chloride solution ; if working in grains, then it will be most convenient to make it of that strength that it just forms a perma- nent lather when 180 grain measures are shaken with 1000 grain measures of the standard calcic solution, equalling water of 8 . Sodmm Chloride Solution 1-648 parts of pure sodium chloride are dissolved in watei-, and the solution made up to 1000 parts. Pure sodium chloride can be obtained by passing through a saturated solution of commercial sodic chloride hydrochloric acid gas j a precipitate of pure sodic chloride falls, which may be collected, and dried in the hot air oven at 260° to 300°. Each cc. contains -001 grm. chlorine, or each grain contains -001 grain chlorine. Sodium Hydrate, Solution for Estimation of Nitrates.— 5G parts of juetallic sodium are dissolved little by little in 1000 parts of water. Sodic Hyposulphite.—One part of crystallised sodium hypo- sulphite in 1000 parts of water. Sodic Nitrite Solution.—-406 part of silver nitrite is dissolved in a little distilled water, and pure sodic chloride is added until no more argentic chloride is thrown down. Dihite with water to 1000 parts. Allow to settle. Then of the clear solution take 100 parts, and dilute to 1000 ; 1 cc. equals -00001 grm. of N^Og ; similarly each 10 grains equals -0001 grain. Starch Solution.—1 part of starch is rubbed up with 20 parts of boiling water. The liquid is filtered, boiled, and after being allowed to stand for twenty-four hoiirs, the clear liquid is .syphoned off. TABLE LV., FOR Hardness in Grain Measures (Page 327). Dngrees of Hardness. Grain Measures. Distilled Water = 0 9 ]. 2 4. o. (5. 7. 8. 9. 10. II. 12. 13. 14. 15. IG. 29 i54 77 99 120 140 160 180 200 220 240 260 280 300 320 340
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