158 MISC. PUBLICATION 5 4 0. U. S. DEPT. OF AGRICULTURE 



with air. This protecting device is used in place of the rubber bal- 

 loons commonly used in the past for this purpose. 



The process of sampling is carried out as follows : A can is placed 

 in the stand, lid uppermost. The bulb (G) is filled with fluid to the 

 cock nearest the puncturing device, and all three stopcocks are closed. 



(TOP VIEW) 



ORSAT APPARATUS 



... °'% 



16 



Metal 



Tube Screwed 



and Welded 



GAS 

 Figure 68.- 



SAMPLING ASSEMBLY 



(TEE) 

 PUNCTURING DEVICE 



-Equipment for the analyses of the atmosphere of 5-gallon cans filled 

 with dehydrated vegetables. 



The puncturing device is forced down against the can. Contact is 

 first made between the can and the stopper, followed by the puncturing 

 of the can. The three cocks are now opened to permit some of the 

 gases in the can to flow into G when the bulb H is lowered. The stop- 

 cocks are then closed. 



For analysis of the gas, a 100-cc. gas burette is used with an en- 

 largement between the and 50-cc. marks, with no intermediate 

 graduations in that range. The rest of the scale is divided into 0.2-cc, 



