PHILADELPHIA 
Bacteriological Incubators 
These incubators are thoroughly well made, and are properly tested and 
retested both during manufacture and just before shipment. The workmanship 
is of the finest, and they are far superior in every respect to the best of foreign 
manufacture in their appearance, durabiUty, exact fitting of parts to prevent 
evaporation of culture media, scientific construction to prevent radiation and con- 
vection of heat, in economy of gas, and in their convenience and adaptation to 
the needs of the bacteriologist. In the manufacture the double copper walls of the 
water space are first perfectly fitted and tested and afterwards the outer wall and 
covering are fitted so that there can be no possible leakage from the water cham- 
ber. The bottoms of the incubators are so constructed that there is no dripping 
from condensation of the vapor given off by the burner. A metal tube traverses 
the wall of incubator, communicating between the gas regulator and bunsen 
burner, to prevent dang:er of fire. These incubators being of domestic manu- 
facture, any part broken or deranged by accident can be immediately repaired. 
The stout copper walls.of water space are thoroughly bound and firmly braced to 
prevent bulging from the enormous weight of the contained water. The water 
space is surrounded by an air space, which is enclosed by a metal wall covered 
with another heavy wall of non-conducting waterproof material, having a very neat 
appearance, and which will not crack in use. Most the larger incubators are sup- 
ported by a strong angle iron frame well braced, bringing them to a level con- 
venient for manipulation and examination of contents. Where specially indi- 
cated, the burner is completely enclosed by a sheet-iron casing to protect the flame 
of the burner from currents of air or sudden gusts. Where the burner is thus 
enclosed, a small door is placed in front, with window for observation or 
adjustment of the flame. 
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