From David Gilmour's The Ruling Caste: Imperial Lives in the Victorian Raj:
In 1870 [Indian Civil Service] salaries were slightly lower than they had been forty years earlier although the cost of living had risen over the same period. More serious for Civilians, however, was the subsequent depreciation of the currency. In The Importance of Being Earnest Miss Prism instructs her pupil Cecily Cardew not to read a chapter on the fall of the rupee because the subject is too sensational and melodramatic for a young girl. It was certainly an undesirable sensation for men who earned a salary in rupees but spent much of it in sterling.
Prussia's defeat of France in 1870 had led to the victors' abandonment of silver and the adoption of a gold-based coinage, an event that affected other currencies and had unlucky consequences for the silver-based rupee, which had no fixed value with the gold-based pound. The result was that the rupee, which had been worth two shillings (a tenth of a pound) in 1870, fell to one shilling and seven pence in 1885, and to below one shilling and threepence in 1892. Although this was an advantage for Indian exports, it was a disaster for Civilians with financial obligations in Britain. A thousand rupees, which had been worth £100, now purchased only £62. Henry Beveridge's salary, which had been the equivalent of £2,640, was by 1886 worth less than £2,000; each pound spent on school fees in England thus cost him thirteen and a half rupees rather than ten. Six years later, the situation was even worse.
Civilians generally reacted to the blow by maintaining their children at school but reducing their own standard of living in India, a course which had the effect of deterring potential recruits to the Service and encouraging early retirement. Since their salary was paid in rupees and their pension in sterling, there was little incentive for Collectors to stay on to enjoy the ever-decreasing extra money. As one junior Civilian reported, 'Most of them say that 700 rupees a month extra [the difference between pay and pension] isn't worthwhile when it entails living in a pestilential country, away from your wife and children, and in a post that takes 12 hours work a day.'
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