262 ON THE EARLY STAGES OF INFLAMMATION 
different animal, the cilia having been ascertained to be in rapid motion on 
a fresh piece of tongue, lint containing liquor ammoniae was held at a short 
distance from it for thirty-three seconds. The cilia very soon grew languid, 
and by the end of the time mentioned had quite ceased to act. The lint was 
at once withdrawn, but no recovery occurred; the operation of the irritant 
had been rather too energetic, and the vitality of the tissue had been destroyed. 
A languid state of the cilia was also produced by placing freshly prepared 
mustard near them, and improvement took place when it had been removed ; 
but the essential oil itself, applied on lint like the chloroform and ammonia, 
though not acting so rapidly as might have been expected, permanently arrested 
the vibratile filaments. The vapour of strong acetic acid, if acting for four 
seconds, caused great diminution of the motion, and in another instance arrested 
it completely in five seconds. I did not, however, see any recovery from the 
effects of this agent, which produced obvious organic injury in the cells. The 
introduction of a portion of the mucous membrane of the mouth into a bottle 
of aerated water for about twenty minutes gave rise to permanent stoppage 
of the cilia, and similar treatment for three or four hours caused disorganization 
of the epithelium, whereas the same period of immersion in ordinary water did not 
arrest the cilia. Powerful interrupted galvanic currents, transmitted for a few 
seconds through a particular spot in a piece of tongue on which the cilia were 
in free movement, abraded a portion of the epithelium there, and arrested 
completely the cilia of adjacent cells still 7m situ, and rendered those of other 
parts of the specimen extremely languid in their action. But the most satis- 
factory results were obtained from experiments with heat, which has the great 
advantage over chemical irritants, that it leaves no material behind it to act 
upon the delicate tissue. On the 14th of December, 1857, having ascertained that 
steeping a piece of the tongue of a frog for five minutes in water of 110° Fahr. 
caused total and permanent cessation of ciliary action and desquamation of 
the epithelium, at g 9™ p.m. I placed a portion of that organ, in which the 
vibratile movements were equable though rather languid, in water at 100° Fahr., 
and retained it there for a minute and a quarter, when it was transferred to 
cold water. On examining it after the lapse of nearly two minutes, I found 
the cilia acting decidedly more briskly than at first, but in the course of the 
next quarter of an hour they flagged very much, and in many parts ceased to 
move altogether. By this time I had fixed the specimen securely at the bottom 
of a glass trough, which I now suddenly filled up with water at ro2° Fahr., 
and on first catching sight of the object, within a quarter of a minute of this 
procedure, found all the cilia absolutely motionless. I then at once drew off 
the warm water with a siphon previously arranged; and no sooner had this 
