6i6 



Journal of Agricultural Research 



Vol. XV, No. II 



S-'RueeED TuBiNH. 



and was therefore adopted. It is based on the principle of the multiple 

 pipette devised by Buck ^ which is used in this laboratory for the distribu- 

 tion of salt solution, complement, etc. 



DETAILS OF NEW DEVICE 



The device (fig. i) consists of a brass tube, i^X inches in length and 

 ^ inch in diameter (outside), which is tapped at both ends to 



permit cleaning 

 should occasion arise. 

 The lumen commu- 

 nicates, in its length, 

 with 12 brass collat- 

 erals set at equal dis- 

 tances apart and at 

 right angles to the 

 main tube. Bach 

 collateral is 2^ 

 inches in length with 

 a X-iiich lumen, and 

 is lined with rubber 

 tubing of sufficient 

 length to project 

 about }4 inch. This 

 free end of rubber tubing is everted over the opening of the metal col- 

 lateral, thus causing a slight constriction of the lumen of the rubber at 

 that point and serving 

 to fit snugly about the 

 glass pipettes to be 

 fitted therein. On the 

 opposite side of the 

 main tube, at the cen- 

 ter and at right angles, 

 is located a single 

 short metal collateral, 

 or mouth piece, to 

 which is attached a 

 piece of rubber tubing 

 for the control of the 

 device and to which a 

 pinch clamp may be 

 applied, although con- 

 trolling by pressure with the forefinger and thumb has been found to 

 be more convenient. 



Fig. I. — General view of device and pipettes. 



Fig. 2. — Holder connected with serum bottles in standard tray. 



1 Buck, John M. a multiple pipbt for thb complement-fixation test. In Jour. Infect. Diseases, 

 . 19, no. 2, p. 267-271, 3 fig., 1916. 



