206 



KEGRETTI AND ZAMBRA, HOLBORN VIADUCT, B.C. 



FIG. 4. 



FIG. 5. 



FIG. 2. 



FIG. 7. 



FIG. 8. 



FIG. 6. 



FIG. 1. FIG. 9. FIG. 3. 



E. BOURDON'S STEAM PRESSURE AND VACUUM GUAGES. 



