> An engineer named E.P. George used them to make measurements of an Australian tunnel in the 1950s. Seems true, but no confirmation if worked at all - https

> An engineer named E.P. George used them to make measurements of an Australian tunnel in the 1950s. Seems true, but no confirmation if worked at all - https://trove.nla.gov.au/search/category/newspapers?keyword=Cosmic%20rays%20measure%20overburden%20of%20tunnel https://trove.nla.gov.au/search/category/newspapers?keyword=...