On a haematozoon in human blood : its relation to chyluria and other diseases / by T.R. Lewis.

  • Lewis, T. R. (Timothy Richards), 1841-1886.
Date:
1874
Catalogue details

Licence: Public Domain Mark

Credit: On a haematozoon in human blood : its relation to chyluria and other diseases / by T.R. Lewis. Source: Wellcome Collection.

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    One of the Hasmatozoa in this woodcut (No. 8) is seen to have preserved the appearance presented during life, it having been instantaneously killed by holding the slide over the fumes of osmic acid—by far the best method I know for preserving the specimens. The blood should be quickly but evenly spread over the covering glass, forming as thin a layer as possible ; the cover is then to be quickly inverted (before coagulation sets in) over the mouth of a phial containing a 2 per cent, aqueous solution of this chemical. When the preparation has turned somewhat brown, remove it and place it on a slide, previously charged with a drop of a saturated solution of acetate of j)otash or soda, when it is ready for mounting, and will keep, I believe, for an indefinite period. To account for the various appearances presented by these Hsematozoa before and after death, which have been just described and figured, may possibly puzzle others as it certainly puzzled me for over two years, although I was constantly in the habit of examining specimens; but, until their existence in the blood had been discovered, by far the greater number of them had been dead, or nearly so, before they came under observ- ation. Having observed that the appearance usually presented by the Hgematozoa, when recently withdrawn from the circula- tion, differed considerably from what was observed after or shortly before death, it was determined to watch these changes from beginning to end, and to note them as they occurred. With this object iu view, a specimen, which appeared to be well developed, was selected out of several found on a quite recently prepared slide, a carefully corrected immersion object-glass was employed, and the examination continued for eight conse- cutive hours. At first the movements of the Haimatozoon were so rapid that little could be detected iu addition to what has been