THE BOOK OF THE LANTERN. 



53 



trated at fig. 22 as being by far the most perfect of any of 

 the blow-through type. 



FIG. 22. 



In selecting such a jet the buyer should be carefal to 

 see that the orifice of the O pipe is sunk within that which 



FIG. 23. 



supplies the hydrogen, as shown at M. In many jets the 

 two pipes are brought to the same level, but the form I 



