undertake operations of a degree of difficulty quite unattain- 

 able previously, even in such inaccessible regions as the 

 interior of the heart. 



And today an immense quantity of fundamental re- 

 search is being done in the attack on the virus-caused dis- 

 eases. Already poliomyelitis is conquered with immuniza- 

 tion (Salk, 1954), and the work on the common cold is 

 approaching a very hopeful stage in its efforts to rid Man 

 of this troublesome ailment. The work on cancer has been 

 quite successful also, with several practical methods of 

 treatment of early-stage cases now available, including 

 X-ray and radio-isotope irradiation of tumours, complete 

 surgical removal of diseased areas, and irrigation of cancer- 

 ous organs with solutions of certain chemical compounds. 



69 



