. Public health laboratory work, including methods employed in bacteriological research, with special reference to the examination of air, water and food contributed . Fig. 7.—Porcelain dish. Fig. 8.—Pestle and mortar. passage of the smaller tube. Cold water is madeto circulate constantly in this outer tube by meansof the tubing which connects its interior with thetap, the water escaping at the opposite end throughthe tubing which conducts to the sink. The coolwater thus constantly kept circulating condenses the HYGIENIC ANALYSIS OF WATER. 7 vapour in the inner tube, at the further extremity o
. Public health laboratory work, including methods employed in bacteriological research, with special reference to the examination of air, water and food contributed . Fig. 7.—Porcelain dish. Fig. 8.—Pestle and mortar. passage of the smaller tube. Cold water is madeto circulate constantly in this outer tube by meansof the tubing which connects its interior with thetap, the water escaping at the opposite end throughthe tubing which conducts to the sink. The coolwater thus constantly kept circulating condenses the HYGIENIC ANALYSIS OF WATER. 7 vapour in the inner tube, at the further extremity ofwhich the condensed vapour finds its outlet and iscollected. A condensing apparatus can be readily improvised,but since either Grahams or Liebigs instruments arecheap (involving the outlay of only a few shillings !) andat the same time are less liable to leak, yield impurities,or to get out of repair, it is better and cheaper to pur-chase one of these. 9. A set ( nest) of glass beakers (fig. 9) and largewatch glass covers for Fig. g.—Nest of beakers. 10. A bell glass cover. 11. Two boiling-flasks or retorts (of about a litrecapacity), one of which is seen attached to the con-denser in figure 25. 12. Glass stirring-rods. 13. A small glass-stoppered bottle (250 ) for thesoap test. 14. Glass funnels for filtration, with wooden support(fig. 10). 15. Glass burettes holding ten cubic centimetres, andgraduated in , and one-tenth of , one of which Hould be mounted upon a w^^^^n stand and should 8 LABORATORY WORK.
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisherphiladelphiablakis
