[Technization of the senses--from uroscopy to urinalysis. The example of urine sugar]

Since antiquity, medical semiotics has been based on signs solely accessible to the physician's sensory perception. In the 19th century, the spectrum of signs was extended by using new techniques and instruments, as well as chemical analytical procedures. Transferring technoscientific methods to the medical area led to a paradigm shift: Qualitative signs, which had been adequate for "humoral pathology", were by no means sufficient for epistemological investigations based on quantifiable data.This paper examines this process of "technization", using the example of measuring sugar in patients' urine. We reconstruct the evolution of technical methods for analyzing urine during the 18th and 19th centuries and show that traditionally oriented physicians and many patients showed a lack of understanding or even disapproval of the new "iatrotechnic" methods. Only very slowly were they willing and able to adjust to a semiotic turn, i.e., the increasing replacement of linguistic signs by abstract data.It is argued that only a complex of compromises--incorporating transdisciplinary receptiveness, professional isolation, economic viability, and sufficient accuracy, handiness, and manageability of instruments--gave rise to the broad acceptance of technical means to measure the amount of sugar in urine.