96 HISTORICAL INTRODUCTION TO CHEMISTRY CHAP. 



FIG. 21 LAVOTSIER'S APPARATUS FOR COLLECTING THE GAS PRODUCED BY 

 HEATING RED-LEAD AND CHARCOAL IN AN IRON RETORT. 



The air could be drawn out from the bell-jar through the small aperture shown 

 at the top of the jar, or it could be removed by means of an air-pump which has 

 not been reproduced in the figure. 



