WEBB, ON A LOOSE CARTILAGE. 1p) 
been completely altered, for there seems no reason to conclude 
that since the raising of the tumulus, at a time when the 
surface of the field was accessible, there had been such im- 
portant changes in the district as would be implied by the 
accumulation of a large body of water, upwards of seven feet 
in depth, and the subsequent drainage of the same. 
Notes of the Microscopican Examination of a Loose 
CartitacEe from the Kner Joint. By W. Woopuam 
Wess, M.D., Lecturer on Histology and Minute Anatomy 
at the Middlesex Hospital. 
Tue cartilage on which these observations were made, was 
removed from the knee-joint of an elderly man in the Norfolk 
and Norwich Hospital, by my friend Mr. Cadge, surgeon to 
that institution. It was of somewhat larger size than is 
usual in such formations, and was of a flattened and elon- 
gated shape. Its general appearance was that of a nodule of 
fibro-cartilage, but the section towards the interior gave rise 
to a rough gritty sensation, and showed a darker and uneven 
surface. When dried, the internal parts were quite opaque, 
and crumbled away if scraped. 
By all the older writers it seems to have been regarded as 
an established fact that the denser portions of these loose 
cartilages were of true bony character; and even in Wedl 
and Rokitansky, we only meet, in reference to them, with the 
vague terms of ossification, cretification and calcification, 
none of which convey any definite information as to the 
exact histological condition of the structures, or their mode 
of growth. 
Before being submitted to me for examination, the spe- 
cimen had been much handled and kept in dilute spirit. It 
was, therefore, not in the most favorable state for ascer- 
taining the nature of its superficial investment ; but I believe 
that epithelium had been present on those parts least exposed 
to pressure, though on the flatter portions there was no trace 
ef such cells. It is only by dealing with the most delicate 
preparations that any accurate knowledge of these growths can 
be arrived at, and even with them a micro-chemical analysis 
1s necessary. 
A very thin vertical section, under a power of 220, brought 
into view the following appearances. On the surface was a 
condensed layer of fibrous tissue which had a_ horizontal 
disposition, and swelled up and became gelatinous with acetic 
acid. This gradually lost all indications of fibrillation, and 
