717 
nga 
(c) Shape effects, —- Charges of various shapes were fired and the 
shock wave studied in various orientations from these chargese These dif- 
ferent shapes were confined to spheres, and to cylinders with different 
ratios of length to diameter. 
(a) Similitude laws, — The relationships between the reading of a 
given gauge and the charge weight and charge=toegauge distance were deter- 
mined, This work was much more difficult due to the fact that it involved 
the absolute level of the various quantities. It was not until the instru- 
mentation was fairly well stabilized that it was desirable to publish such 
results, and even then it has been necessary to revise the absolute levels 
reported on occasion, 
(c) Multiple charges, —- A study of the effects of subdividing a charge 
into smaller units of the same total weight as a given single charge, and 
the comparison of the results so obtained, was carricd out in preliminary 
experiments. In this work it was extremely important to consider the 
various measured parameters in different directions from the charge, 
(£) Surface effects, -— The effect of the air-water interface and the 
bottom in producing reflected rarefaction and pressure waves has been 
studied under various experimental conditions. 
In Part III the type of work which was done on the RELIANCE has been 
summarized. The details of the results are being reported elsewhere {15]. 
