302 rREPARIN(; liUTTER FOR MARKET 



" It will be seen from this table that all of the untreated 

 tubs became moldy. Of the six tubs treated with hot brine, 

 one was Ixadly molded, one was slightly molded and one had 

 mold on the outside. Of the six tubs soaked in the brine- 

 formaldehyde mixture, one was badly molded. None of the 

 tubs coated with paraflin showed any mold whatever, and the 

 same was true of those dipped in paraffin. 



" To treat tubs by the brine-formaldehyde method or the 

 hot-brine method a vat should be made large enough to hold 

 submerged the tubs used in one day. The cost of either of these 

 two methods is insignificant as the bath may be used repeatedly. 

 The objections to these two methods, in addition to their inef- 

 ficiency, would probably be found in the discoloring of the wood 

 and, with the hot brine, in the excessive weight and swelhng of 

 the tub." 



Paraffining of Tubs. — From the investigations made it would 

 seem that the most efficient method of treating tubs or boxes 

 for the prevention of mold is to paraffin them on the inside. 



Before tubs are paraffined they should be thoroughly 

 steamed. In extreme cases, where tubs are very open, it may 

 be necessary to soak them, but only in such cases. Whether 

 soaked or not, the tubs should be steamed just before paraffining 

 them. This swells and tightens the tub, and heats the wood and 

 opens its pores so that the paraffin will penetrate it sufficiently 

 and at the same time form a nice, smooth coating. The par- 

 affin should be heated to a temperature of about 250° F. If 

 much below this it is apt to cause the coating to be thick and 

 patchy, and if much above it is likely to soak into the wood and 

 not form a proper coating. The easiest way to heat the paraffin 

 in a creamery is to place a steam coil in the bottom of the 

 paraffin tank with a valve or dripcock on it to allow the escape 

 of condensed steam. 



Where the work is done in a small way, the paraffin can be 

 apphed in one of two ways — either by means of a brush or by 

 pouring some paraffin into the tub, rotating it to cover the whole 

 surface and then placing it mouth downward to drain the sur- 

 plus paraffin from it. But in a creamery of any size a suitable 



