30 CIRCULAR 3 6 9, U. S. DEPARTMENT OF AGRICULTURE 



Several types of metal vaults (fig. 24) can be purchased knocked 

 down ready for assembling. These are excellent in every way. 

 Highly satisfactory vaults can be constructed of concrete, brick, or 



Figuke 24. — Two types of metal vaults such as can be purchased or built accord- 

 ing to space and commodity need. These vaults are used for treating the day's 

 arrival of fur coats offered for summer storage. After an overnight fumigation 

 in these vaults the furs are removed to large permanent storage vaults. 



Figure 25. — Two outdoor fumigation vaults under one roof, built of brick, finished 

 on the inside with Keen's cement, and equipped with doors shutting against 

 rubber gaskets to prevent gas leakage. Note ventilators in roof to aid in 

 ventilation when lighter-than-air gas is used. (Photograph by Perez Simmons.) 



hollow tile, The brick (fig. 25) and hollow-tile (fig. 26) vaults 

 should be finished inside with a layer of Keen's cement and one or 

 two coats of paint. Wooden vaults with a metal lining are also 



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