Serological Technique (Contd.)

as the full test. It is performed as follows The apparatus.? (i) Small wooden racks about 12^ inclies by about 1^ inches (at the bottom) by 1^ inches, to hold 18 miniature test tubes, the bottom shelf painted black and the rest white, and the top numbered for the tubes. Each rack is also numbered, (w)' Durham's fermentation tubes measuring about 5 cm. by 8 mm. with internal diameter of 6 mm.A fermentation tube not admitting a pipette should be rejected. {Hi) Antigen-suspension vials* measuring 5? by l\ cm. as prescribed for the regular test, (iv) A 0.1 c.c. pipette graduated to the tip in 0.01 c.c. divisions for distributing antigen dilution. A Kahn pipette graduated to the tip or a Wright's pipette calibrated with mercury may be used. The pipette is worked with a teat. (v) Thin 1.0 c.c. pipettes graduated to the tip in 0.1 c.c. divisions for distributing serum and saline, (vi) Incubator registering 37?C. (vii) A magnifying glass. Items i to vii are shown in the photograph.