'Impossible to provide an accurate estimate': the interested calculation of the Ottoman public debt, 1875-1881.

When the Ottoman Empire defaulted on its public debt in 1875, British bondholders launched a campaign to win government intervention on their behalf. This article interprets the unprecedented success of this campaign as a matter of knowledge production. Mobilizing the newly established Corporation of Foreign Bondholders as a kind of 'centre of calculation', bondholders argued that they deserved assistance because of the unique size of the Ottoman default and the proportion of it that was held by British subjects. Yet neither of these numbers was easily calculated. In fact, influential bondholders worked closely with accountants and members of the Statistical Society to devise an accurate method for quantifying the Ottoman debt - and concluded that such a method did not exist. Historians of quantification and accounting have argued that the scientific status of nineteenth-century accounting depended on its disinterestedness. In the case of the Ottoman default, however, calculation was understood to be inseparable from material interest and political debate.