Abstract
I TOLD you I had something more to say about the spectrum of blood, and this is not only an instance of the way in which the spectrum helps us in several important questions that, at first sight, do not seem at all connected with each other, but it shows the enormous power of research that is open to us. The colouring matter of blood, for instance, is found, like that of indigo, to exist in two perfectly different states, which give two perfectly different spectra. The colouring matter of blood is indeed capable of existing in two states of oxidation, which are distinguishable by a difference in colour, and also in their action on the spectrum. They may be made to pass one into the other by suitable oxidising and reducing agents; they have been named by Professor Stokes, their discoverer, red and purple cruorine. Previous to the introduction of spectrum analysis, red and purple cruorine were perfectly unknown. Further, if by means of a spectrum microscope, such as I have already described, a blood-stain is examined, Mr. Sorby asserts that the thousandth part of a grain of blood,—that is to say, a blood-spot so small that it only contains 1/1000 of a grain, is perfectly easy of detection by means of this new method, and he has shown that its presence may be easily proved in stains that have been kept for a long time, and recognised even after a period of fifty years.
Article PDF
Rights and permissions
About this article
Cite this article
LOCKYER, J. On the Spectroscope and its Applications VIII. Nature 8, 10–12 (1873). https://doi.org/10.1038/008010a0
Issue Date:
DOI: https://doi.org/10.1038/008010a0