VELOCITY OF THE CIRCULATION. 
operation ; 1 therefore send the lollovving account of cases, where 
that operation has been successful in cattle. About the end of 
June, 1827, I received a letter- from i\lr. William Laing, of 
Banchory, Aberdeenshire, an old pupil, requesting my advice, re¬ 
garding the propriety of amputating the leg of a valuable milch 
cow, which had met Vvdth a severe compound fracture of the 
lower end of the metacarpal’ bone of the off fore,.leg; in con¬ 
sequence'of which, sloughing had taken place to such an extent, 
that there did not appear to be a chance of saving the limb. 
Under such circumstances I stated that it appeared to be the only 
means likely to * save the animars life, (which was a matter of 
considerable importance, as the animal was a great favouiite). 
And on the 20th September following, I had another letter from 
the same person, from which I give the following extract: he says, 
I performed amputation upon the cow on the 7th July : after 
having properly secured the animal, and 'applied a tourniquet 
above the carpus, I made a circular incision through the integuments 
round the leg, a little below the carpus, and having separated 
the skin so as to allow, of its being pushed up a little, I cut 
through the sinews, and lastly sawed otf the stump : the parts are 
now completely whole, although she has been going at grass all 
the time, and, now that she has got the advantage of a cork stump, 
makes a wonderful shift for herself, and yields a good supply of 
milk to her owner.’’—Mr. Dodds, Kirkcaldy, informs me that he 
has also amputated the leg of a two year eld heifer. And I was 
informed of a third case, on Saturday last, in which the limb was 
removed above the tarsus; but as it had only been done a few days 
before I heard of it, and as I did. not get the particulars, I refimn 
at present from stating any thing further respecting it. 
I am, Sir, 
Your most obedient servant, 
Edinburgh^ 20th August, 1828. William Dick. 
THE VELOCITY OF THE CIRCULATION OF THE 
BLOOD. 
(Communicated by M.) 
M. HERING, of Stuttgart, has made some novel experiments on 
the velocity of the circulation of the blood in the horse. The 
subject had been often discussed, and many ingenious and elabo¬ 
rate calculations had been formed, but the result had been uni¬ 
formly unsatisfactory. If tlie action of the lieart be the moving 
