18050 str (112)

Bi i ||B B vixconietcr,¹ which is cssentiallya mndilu.ilum of tha Bfflgkm I Plaitometor," TJiii iniil rumtmt, which    i lancii bal by Scott BJfiir Mil

CfOWtheł, COlJiWt# nl tW0 pipottCI, (lic Jowcr P whi(,h ;ur t ui ofi _;ilj(i ijyfli _;it liffht unglcs and

• Ollln ihil Ir i Hic ciirlj yf _;J <;:tpjll;ii y I llllti DI ‘iWllt^¹¹ ihiiii'ti',i')ti‘,. I h<' whi)h' ihwicc M hcilcnml which c-m br rointed, §o lh:i.l tlicie ii no t/yrJro»taj^,c pfcMUre dillctcricc bałwani tha fliatGflflllfl ^,Ł

Itrwlotl'

modi&ed frotn that dcscnbsd by Grccn. The air displaced by the infiowing pastę is allowed to escape throngh a senes of standardised capiUary tobes.

Air being a trae fluid, the ratę of flow of the air and hence of the pastę, is proportional to the air pressure between the bulb and the capillaries, a pressnre which is, of course, smali compared with the drivmg pressure, and which can be measured on a sensitive alcohol manometer (Fig. 13)-With this apparatus a complete flow curve can be obtained in a few minutes, and the capillaries are easily interchangeable. The variable air-leak makes possible the measurement of a very wide rangę of flow-rates on a single manometer. The whole apparatus can be set up in a thermostatic water bath, for temperaturę control. It has been success-fully used for soils, ceramic clays, drilling muds, paints and dairy products such as cream.

BIBLIOGRAPHY

Bmw. " A Monograph on Viacometry," 1931. Oxford Univeralty Prosa.

Binuham mul Mubray. J, Amor. Soc. Test. Mats., 1923, XXIII., 633.

IłiNi.iiAM and Kojucktaon. Koli, Zeits., 1929. XLVII., t. Campbbll, J. Soc. Cham. Ind., 1938, LVII.

Dillon mul Johnson, Physics, 1933. IV., 225. loouiNouęn (ind Siuiouz. Z. Phys. Chem., 1922, CIV., 233. Gniioouy, Baswimi.kk (ind LAMPBRT. llheol., 1929, 1., 30. Hatichbk. " Viscosily of l.ląuids," 1928. Holi.

IIaihciihk and |ank, Holi. Zeits., <92(1, XXXIX., 300. Mumimimuy .md IIathciikk. Proc. Jioy. Soc. (A), 191O, XXXVIII.,

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