Buddy diving just before and after the Second World War. After the invention of the "aqualung" by Cousteau and Gagnan, the first commercially underwater breathing apparatus became available for sale for sporting purposes in the late 1940s. As the new sport of scuba diving rapidly expanded through the 1950s, several sporting organisations—notably the YMCA—began programmes to train swimming enthusiasts in this new aquatic pastime, and began to codify what they believed were proper practises for this expanding sport. The YMCA considered the buddy system a useful corollary to the "never swim alone" rule of their swimming and lifesaving programmes. Cousteau himself independently
James May's 20th Century chronological order. The programme is now shown on Eden, Yesterday and Dave. The theme tune is called "The Long Boot", by Jeff Knowler. Sam Wollaston writing for Guardian Unlimited described James May's 20th Century as "essentially Top Gear, masquerading as something educational" but conceded that if "teaching history can be achieved through Top Gear, then maybe that's not such a bad thing". The New Statesman thought that James May was "ill-suited to the task in hand" and described the biggest problem as May being unable to "put his wretched motors behind him". The Lancashire Telegraph wrote positively of the show