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for works of repair. On the contrary, in living bodies, the more 
important the work of reparation, the more imperatively must every 
function go on with energy and regularity. The physical enquirer, 
dealing with inanimate things, could make any experiments he chose ; 
but the physiologist must accept accidents and their history in 
determining the laws of healing. 
The enquiry, ‘‘ What is healing ? ” involved us in others. What is 
growth? especially as respects the first formation of blood vessels in 
the embryo. What is inflammation? If dust entered the eye, 
inflammation arose ; if a thorn pierced the finger, and, breaking, left 
a piece behind, there would be inflammation and suppuration ; if a 
dead part was to be thrown off, the phenomena were inflammation, 
- suppuration, and granulation. 
Granulations were characteristics of healing. They consisted of 
myriads of newly-formed blood vessels, and the coats of the vessels 
were composed of globules or cells, not distinguishable from the 
colourless cells of blood. 
It was in a vast assemblage of globules or cells, not distinguish- 
able from the globules in the blood, that new vascular tissue, new 
blood vessels, were formed. Exactly the same materials and phe- 
nomena as might be seen at the earliest period of growth. 
Some years ago an American gentleman exhibited a Hydro- 
incubator in London. He allowed Dr. Addison to-purchase eggs at 
every period of incubation and to examine them. On one occasion an 
ege was opened after 70 hours, and the parts were seen covered by 
innumerable embryonic vessels, which had nothing but globules in 
their structure. Without any further disturbance, a watch glass was 
placed over the broken part of the shell and the egg returned to the 
warmth of the incubator. Twenty hours after, a great number of new 
and collateral vessels, strangely divergent from the natural ones, had 
_ been formed, to meet, as it were, the damage done by the premature 
breaking of the shell. All these vessels had nothing but globules in 
their composition and were easily obliterated by moving the point of a 
needle in their midst, 
Other facts of healing might be compared with embryo growth. 
If a tendon were ruptured, or a bone broken, great heat attended the 
first stages of reparation. In all parts the heat of the first stage of 
healing was above that of the neighbouring parts. These facts 
