Experiments and observations in order to ascertain the means employed in the animal economy, in the formation of bone / by John Howship.

  • Howship, John, 1781-1841.
Date:
1815
Catalogue details

Licence: Public Domain Mark

Credit: Experiments and observations in order to ascertain the means employed in the animal economy, in the formation of bone / by John Howship. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    18/41 (page 17)
    extremely vascular, and of a deep crimson colour. On removing the scalp, a part of the superior margin of the frontal bone, covered by its mem- brane, was cut out with a pair of scissars, and laid upon glass to dry. On examining it by the solar microscope, many small portions of bone were ob- served, which had been deposited in points entirely detached from the larger ossific radii. These mi- nute nodules of ossific matter, together with the ra- diated margin of the bone, were comparatively thick, but towards the central part of the bone, the plate was thinner, and consequently more transparent. This specimen was examined with attention, first as an opaque, and then as a transparent object, for each of these modes has its advantages. To procure a perfectly exact outline, and to shew the precise figure of all the little ossific radii, it was necessary that a strong light should be transmitted; and on the other hand, to ascertain the superior thickness of the smaller masses of the ossific mat- ter, contrasted with the more evenly disposed structure towards the centre of the bone, as well as to shew the earliest appearance of the phosphat of lime, which is deposited in minute granules dis- persed through the intermediate cellular structure of the membranes, required that the surface should have a brilliant light cast upon it obliquely, for when the light was transmitted, the smaller gra* nules were not discernible. B