<%@ page language="java" contentType="text/html" %> <%-- Include common initialisation code --%> <%@ include file="/arch/common.jsp" %> <%-- The current tab --%> <% String currentTab = "Research"; %> <%-- Content of navigation pane --%> <%@ include file="nav.jsp" %> <% showCurrentLink=true; %> <%-- Current navigation location --%> <% String currentNav = "Reports and Theses"; %> <%-- Include the code for the document header --%> <%@ include file="/arch/header.jsp" %>

Research Report CS-RR-420

<%-- Include the code for the lines and navigation --%> <%@ include file="/arch/middle.jsp" %>

Charles Care, The Analogue Computer as a Scientific Instrument

The users of analogue computing employed techniques that have important similarities to the ways scientific instruments have been used historically. Analogue computing was for many years an alternative to digital computing, and historians often frame the emergence of analogue computing as a development from various mathematical instruments. These instruments employed analogies to create artefacts that embodied some aspect of theory. Ever since the phrase 'analogue computing' was first used in the 1940s, a central example of analogue technology has been the planimeter, a nineteenth century scientific instrument for area calculation. The planimeter mechanism developed from that of the single instrument to become a component of much larger and more complex instruments designed by Lord Kelvin in the 1870s and Vannevar Bush in the 1920s. Later definitions of computing would refer to algorithms and numerical calculation, but for Bush emphasis was placed on the cognitive support provided by the machine. He understood his 'differential analyser' to be an instrument that provided a 'suggestive auxiliary to precise reasoning' and under the label 'instrumental analysis', classified all apparatus that 'aid[ed] the mind' of the mathematician. Rather than placing emphasis on automation, Aan analogue computer provided an environment where the human investigator was far more involved in the computation process. This paper will argue that the analogue computer can usefully be considered as a scientific instrument. The role of the analogue computer as a scientific instrument will be investigated from the perspective of the users' techniques and applications. The study will particularly focus on the users' approach to the planimeter, the differential analyser and the electronic analogue computer.

Download

cs-rr-420.pdf

Citation

An edited form of this report has been published in the following conference proceedings. The published paper may be cited as:

C. Care, 'The Analogue Computer as a Scientific Instrument', in B. Grob and H. Hooijmaijers (eds), Who Needs Scientific Instruments?, Museum Boerhaave (Communication 315), Leiden, 2006, pp 265-269. ISBN: 90692-158-2.

<%-- Include the code for the document footer --%> <%@ include file="/arch/footer.jsp" %>