826 



1,65 cm. bore, which is calculated to resist a pressure of4000atm 

 and is suspended on the ceiling bj means of rods. At the bottom 



Fig. la. 



L is closed by a shutter piece M, the construction of which we 

 shall discuss presently. Jf is bored through, and this boring terminates 

 in a steel tube ^V (fig. 11), to which the glass observation tube i 



IS 



Fig. lb. 



Fig. 8. Cock H. 



