 In June 1933 Massey became an independent lecturer in Mathematical Physics at the Queen 's University of Belfast . He was the only member of the department until R. A. Buckingham arrived in 1934 . Despite having to give nine lectures a week , he found time to write his second book , Negative Ions ( 1938 ) , and began working on upper atmospheric physics . Frustrated with the tiresome and time @-@ consuming process of calculation , he had his physics workshop superintendent , John Wylie , build him a small @-@ scale differential analyzer , an analog computer that could solve differential equations , for just £ 50 . This was used to solve problems related to low temperature helium , and the photo @-@ ionisation of oxygen in the upper atmosphere . 
