1887.] Mr A. Rankine on the Thermal Windrose. 
419 
W., and N.W., attains its minimum temperature in January, and 
each of the directions, N., N.E., E., and S.E., in March; while all 
the directions except N.E. and N.W. have their maxima in July, 
the two exceptions occurring a month later. 
8. On Ferric Ferricyanide as a Reagent for Detecting Traces 
of Reducing Gases. By Professor Crum Brown. 
The brown solution obtained when solutions of ferric chloride 
and potassium ferricyanide are mixed, which may be regarded as 
containing ferric ferricyanide, is, as is well known, very readily 
turned blue by reducing agents, Prussian blue or Turnbull’s blue 
being formed. The author uses strips of filter paper dipped in the 
freshly prepared solution to test for traces of reducing gases, such 
as sulphuretted hydrogen, sulphurous acid, &c. As nitrous fumes 
also blue the brown solution, reducing it, traces of them can be 
detected by using together a piece of paper prepared as above and a 
piece of iodised starch paper. 
9. On the Compressibility of Water, of Mercury, and of 
Glass. By Professor Tait. 
19. An Account of some Experiments which show that 
Fibrin-Ferment is absent from circulating Blood- 
Plasma, and which support the view, first advanced by 
Sir Joseph Lister, that the Blood has no spontaneous 
tendency to Coagulate. By Professor John Berry 
Hay craft. 
(Abstract.) 
Sir Astley Cooper and Turner Thackrah taught that blood was a 
fluid tending to coagulate, but inhibited from doing so by the living 
vascular walls. This view is erroneously ascribed to Briicke, who 
himself only professes to support it. 
Sir Joseph Lister considers that blood of itself does not tend to 
