This chapter begins with surveyors Alexander and James Gerard, and their attempts to prove that they had climbed higher than Alexander von Humboldt. In examining the measuring practices of East India Company surveyors, the chapter especially deals with moments when scientific instruments were found to be inadequate. These are revealing of the importance instruments played in establishing scientific authority in a world in which the senses were unreliable. This chapter firstly considers responses to damaged instruments, and attempts at repair. This is followed by a discussion of surveyors’ fieldbooks and inscriptive practices. It concludes with an examination of ongoing problems – both conceptual and material – with instruments designed in Europe by those with no experience of the Himalaya. The chapter argues that the staggered recognition of the true scale of the Himalaya reveals multiple levels of displacement in scientific practice: between those in the mountains, those in Calcutta and those in London. In so doing, it emphasises the laboriousness of the instrumental measurements necessary to impose, if incompletely, a form of universality that made global comparisons possible.