Although the family in Bathgate strained every nerve to keep James well supplied with the necessary funds as a student, they were not able to place him in such a pecuniary position as to make it unnecessary for him to exercise economy: He appears to have been very careful indeed of the money which he had; much more careful than when he reckoned his income by thousands. He kept methodical accounts of his expenses down to the most trivial items, and regularly submitted them to his family. His cash-book opened with the following quotation from a small book called the "Economy of Life," which figures at a cost of ninepence:--"Let not thy recreations be expensive lest the pain of purchasing them exceed the pleasure thou hast in their enjoyment"; and to this he added:-- "No trivial gain nor trivial loss despise; Mole-hills, if often heaped, to mountains rise. Weigh every small expense and nothing waste; Farthings long saved amount to pounds at last." It is easy to see here the imprint of a well-known national characteristic, from which, however, he completely shook himself free when prosperity came to him. His share of the rent of the Adam Street lodging amounted to only three shillings a week. The entries in the cash-book show how frugally he lived and how every spare sum was devoted to the purchase of books. His library, the foundation of much of his encyclopedic knowledge, was a curious mixture. Adam's "Antiquities," Milton's Poems, Byron's "Giaour" and "Childe Harold," a Church Bible, Paley's "Natural Theology," Fife's "Anatomy," and "The Fortunes of Nigel," were amongst those entered as purchased. The daily entries were such as the following:--"Subject (anatomical), L2; spoon, 6d.; bread and tart, 1s. 8d. Duncan's Therapeutics, 9d.; snuff; 1-1/2d.; Early Rising, 9-1/2d." He followed out the usual student's custom of the day of learning dispensing by serving for a time in a chemist's shop. The late Dr. Keiller, of Edinburgh, used to relate how, while he himself was so employed in a chemist's shop in Dundas Street, one day "a little fellow with a big head" was brought in and entered as a pupil by a relative. The little fellow was Simpson, and no sooner was he left in the shop than he sat down with a book upon drugs, and turning to the shelves took down drug after drug to read up. The prompt industry of the big-headed fellow deeply impressed Keiller.