Sterilising. (>!) 



scending with the hood or cover will exactly dip into 

 this milk (see Fig. 18), and consequently the read- 

 ing 011 this thermometer \\ill give a fair indication 

 of the degree of heat attained in all the bottles. 

 When bottles of different sizes are sterilized simultan- 

 eously, then one of the largest sized bottles must be 

 used to hold the thermometer bulb, for we must take 

 account of the prescribed time for sterilizing from 

 the time the largest bottles in the aparatus have 

 reached the desired degree of heat. 



Whatever time may have been fixed upon for the 

 various periods of sterilization or combinations of 

 alternate heating and cooling, they should, however, 

 be closely adhered to, as every variance therefrom, or 

 negligence in this respect, will at once tell on the 

 keeping qualities of the milk. 



Let us, however, bear in mind that all attention 

 and neatness during the process of sterilization is 

 wasted and futile, if the milk has not been produced 

 and handled with the utmost cleanliness, and here, 

 again, we may observe that it is not so much the 

 bacteria floating in the air that have to be feared and 

 guarded against, than those that cling to matter of 

 every description : vessels, utensils, hands, etc. The 

 prime object to be attained, after having applied the 

 proper sterilizing, is the hermetically sealing of the 

 milk bottles before the outer air can come into re- 

 newed contact with the contents. In what degree 

 this last and most important requisite is attained, de- 

 pends naturally on the efficiency of the closing r.r- 



