ABSTRACT
In the days when Strathclyde University was still called the Andersonian, the other place in Glasgow was sometimes jocularly known as the Thomsonian, so numerous were the Thomsons among its professors. In the session 1848-9 there were five of them, including William Thomson and his father. The Senate of Durham University, sleepily approving syllabuses and degree regulations on a warm afternoon nearly 40 years ago, were roused by an unexpected objection from the Professor of Divinity, Canon A M Ramsey, who later became the Archbishop of Canterbury. A sound wave consists of alternate compressions and rarefactions. A liquid can withstand the compressions easily enough, but severe rarefaction will produce an empty space, which will be quickly filled by vapour or dissolved gas emerging from the liquid to form a little bubble.
