472 



CENTRAL SCIENTIFIC CO., CHICAGO, U. S. A. 



No. 12938. 



No. 12940. 



12916. STOP-COCKS, Glass, three-way lamp blown form. 



Bore of stopper, mm 



Each . 



No. 12942. 



1 



4 

 2.75 



$1.80 2.00 



12918. STOP-COCK, Glass, same as No. 12916, but with capillary tubes. Bore of stopper, 2 mm 2.25 

 12920. STOP-COCK, Glass, four- way. Bore of stopper, 2 mm 2.50 



12922. STOP-COCKS, Glass, three-way, with downward outlet through stop-cock plug. 



Bore of stopper, mm 1 



Each 2.65 



12924. STOP-COCKS, Glass, three-way, same as No. 12922, but with capillary tubes. 



Bore of stopper, mm 



Each . 



1 

 3.00 



o 

 2.75 



o 

 3.15 



12928. 

 12930. 



STOP-COCK, Glass, two-way, with plug bored at an angle. Bore of stopper, 2 mm 1.75 



STOP-COCK, Glass, two-way, same as No. 12928, but with capillary tubes. Bore of stopper, 

 2 mm 2.15 



12932. STOP-COCKS, Glass, three-way, with plug with two holes bored at an angle, and with two out- 

 lets on one side. 



Bore of stopper, mm 2 4 



Each 2.50 4.40 



12934. STOP-COCKS, Glass, three-way, same as No. 12932, but with capillary tubes. Bore of stopper, 

 2 mm 3.00 



12938. STOP-COCKS, Glass, two-way, with mercury seal, and plug bored at an angle. 



Bore of stopper, mm 



Each 



2 

 4.00 



12940. STOP-COCKS, Glass, Burette, with outlet drawn to a tip, for attaching to burettes. 



Bore of stopper, mm 1 



Each 1.40 



12942. 

 12946. 



4 

 5.50 



2 

 1.50 



STOP-COCK, Glass, Presenius form, for burette tips. With inlet tube bore, 5 mm; outlet bore, 

 2 mm 1.20 



STOP-COCK GREASE, for lubricating and preventing leakage. Heavier and more resistant to 

 reagents than vaseline per ounce bottle .25 



