SUMMARY 4^ 



Summary. 



In this paper the following additions to the knowledge of com- 

 pressibility are made : 



i. The practical errors of many previously used methods have been 

 demonstrated. 



2. New methods have been suggested which are applicable to nearly 

 all solids and liquids. 



3. With the help of these methods, the compressibility of bromine, 

 iodine, chloroform, bromoform, carbon tetrachloride, phosphorus, 

 water and glass have been determined by reference to mercury, in 

 most cases as far as 500 or 600 atmospheres. These are recorded on 



P- 43- 



4. From some of these the compressibility of liquid chlorine has 



been inferred. 



5. Approximate determinations of the heats of compression of water 

 and mercury have been made. 



6. A new manometer for calibrating high pressure gauges is pro- 

 posed. 



7. The word megabar is suggested as a convenient name for the 

 pressure of a megadyne on a square centimeter, and the use of this 

 absolute standard is urged. 



8. The compressibilities of the substances named above have been 

 compared with regard to their relative decrease with increasing pressure. 

 It is pointed out that usually the greater the compressibility the greater 

 is its decrease with increasing pressure. 



