After a brief period of unemployment, he was hired as a master at the Collegiate School in Leicester to teach drawing, mapmaking, and surveying. Wallace spent many hours at the library in Leicester: he read "An Essay on the Principle of Population" by Thomas Robert Malthus, and one evening he met the entomologist Henry Bates. Bates was 19 years old, and in 1843 he had published a paper on beetles in the journal "Zoologist". He befriended Wallace and started him collecting insects. His brother William died in March 1845, and Wallace left his teaching position to assume control of his brother's firm in Neath, but his brother John and he were unable to make the business work. After a few months, Wallace found work as a civil engineer for a nearby firm that was working on a survey for a proposed railway in the Vale of Neath.