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ly diluted to allow of regular normal breathing throughout the whole administration.
As long as these conditions are fulfilled, the fall of the blood-pressure is regular,
and the heart's action and the pulse are invariably regular also. We proved that any
irregularity of the heart or of the pulse under chloroform is a certain sign of chloroform-
poisoning, either from direct overdosing or from overdosing through abnormal or irre-
gular respiration. Of normal anæsthesia with regular breathing and without poisoning, which
is, in practice, all the chloroformist has to produce, the pulse can never be any test whatever.
It is only a test of irregular breathing or of overdosing, and it is, therefore, no less dangerous
than useless to take it as a guide.
" Such is a very brief outline of the conclusions and results arrived at by the Hyderabad
Commission. It would be an insult to your common sense to exaggerate them, or to
pretend that without further amplification they define the whole position with regard to
chloroform. Undoubtedly they go a very long way towards doing so, but the old question still
remains unanswered. That question is, does chloroform affect the heart directly ? This
question is inextricably mixed up with the cause of the fall of the blood-pressure under
chloroform, and in order to answer it the cause of this fall must now be determined. If
chloroform in any way whatever directly weakens the heart, it is clear that its administration
can never be free from risk. Clinically I K n o w t h a t i t d o e s n o t w e a k e n t h eh
e a r t , b e c a u s e I o r
anybody else can produce normal amæsthesia with chloroform, with regular breathing and
without overdosing, entirely without risk. This fact, however, will never convert the profession;
and though I have often been annoyed during the past eighteen months because our results
have been so little acted upon, I now see that it is unreasonable to expect the profession to
accept them until the fall of blood-pressure under chloroform is fully and satisfactorily
accounted for. Last year, I had the honor of an interview with Professors Michael Foster
a n d G a s k e l l a t C a m b r i d g e , a n d t h e y e x a m i n e d t h e t r a c i n g s o f t h e H y d e r a b a d C o m m i s s i o n ' s e x p r i m e n t s . P r o f e s s o r F o s t e r l o o k e d o v e r t h e m f o r a l o n g t i m e w i t h o u t s a v i n g a w o r d . A t
last he stated his opinion that the one thing brought out by the whole of the tracings is that
the blood-pressure is lowered by chloroform, it is by all anæsthetics, and that this
appears to indicate danger to the heart ; but be added, 'against this we must remember that
when a poison is introduced into the system, everything that happens afterwards is
of necessit y in the nature of a safeguard.' Apart from vagus stimulation, there are
two possible ways of lowering the blood-pressure : one by weakening the heart, and
the other by vaso-motor dilatation—dilatation of the small arteries. If the lowering
of the blood-pressure under chloroform were due to direct weakening of the heart, it is clear
that a patient under chloroform would be in a gradually increasing state of syncope and
that the fall of blood-pressure would be in itself a danger, and this is opposed to the facts
that there is no danger in normal anæsthesia and that there is absolutely no resemblance
between anæsthesia and syncope. But if the fall is due to relaxation of the vaso-motor
system of muscles and consequent dilatation of the small arteries, it must be absolutely
harmless ; and in accordance with Foster's principle it ought to be a safeguard. If we
carefully consider the effects of chloroform, we find they are as follow : As consciousness is
abolished under chloroform, first the systemic muscles are relaxed and sent to sleep, and then
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