131 
of Edinburgh, Session 1880-81. 
It appears from this investigation that Angstrom’s method, when 
applied with proper precautions, is theoretically capable of giving 
very good results. But it is probable that, in practice, the thermo- 
meters will have to he supplanted, by thermoelectric junctions and 
a good dead-beat galvanometer. The best thermometers, when 
employed for rapidly varying temperatures, work by sudden starts. 
6. Note on a Simple Method of showing the Diminution of 
Surface Tension in Water by Heat. By Prof. Tait. 
A hot bar of iron was brought near the surface of a thin sheet of 
water covered with Lycopodium seed. The effect was precisely 
similar to that produced by ether vapour. 
7. On the Cell-Walls of Hepatic Cells. By John Berry 
Haycraft, M.B., B.Sc., E.E.S.E., Senior Demonstrator of 
Physiology in the University of Edinburgh. 
Since Henle and Purkinje first described the cells which form the 
great mass of the liver, microscopists have maintained that these are 
what are termed “naked protoplasts” — that is, they possess, like 
the white blood corpuscle, no differentiated cell-walls. I may 
mention the names of Dr Lionel Beale, Ewald Hering (“Strieker’s 
Histology,” section on the Liver), and Dr Klein (“Atlas of His- 
tology”), who all agree in denying its existence. Indeed, the absence 
of this structure is emphatically insisted upon in most works on 
microscopical anatomy. 
If a liver-cell be examined with a power of about 300 diameters, 
it is seen to be a granular mass, of a somewhat spherical shape, 
containing a very distinct nucleus and nucleolus. The granules are 
but the optical expression of a delicate reticulum or stroma, which 
may be seen as such on using a higher power. 
If a section of hardened liver be examined, the cells are seen to be 
polygonal from mutual compression, and both in the hardened and 
fresh condition they are bounded by a distinct and well-defined 
contour. 
Nevertheless, there is nothing which would lead an observer to 
