 During the summer of 1887 , Bruce travelled north to Edinburgh to attend a pair of vacation courses in natural sciences . The six @-@ week courses , at the recently established Scottish Marine Station at Granton on the Firth of Forth , were under the direction of Patrick Geddes and John Arthur Thomson , and included sections on botany and practical zoology . The experience of Granton , and the contact with some of the foremost contemporary natural scientists , convinced Bruce to stay in Scotland . He abandoned his place at UCL , and enrolled instead in the medical school at the University of Edinburgh . This enabled him to maintain contact with mentors such as Geddes and Thomson , and also gave him the opportunity to work during his free time in the Edinburgh laboratories where specimens brought back from the Challenger expedition were being examined and classified . Here he worked under Dr John Murray and his assistant John Young Buchanan , and gained a deeper understanding of oceanography and invaluable experience in the principles of scientific investigation . 
