RECENT ADVANCES IN SCIENCE. 559 



one of the pleasantest and most lasting recollections of my visit to Ken- 

 sington. The most competent witness of Huxley's earliest period of 

 development, Professor Foster, presented in the first of these lectures 

 a picture of the rapidly increasing extension of the biological knowl- 

 edge which must have excited not only our admiration but also the 

 emulation of all who study medicine. Upon me the duty is incumbent 

 of incorporating with this presentment the newer strides of knowledge 

 and of stating their influence upon the art of healing. So great a task 

 i.> this that it would be presumptuous even to dare to attempt its accom- 

 plishment in a single lecture. I have decided, therefore, that I must 

 confine myself to merely sketching the influence of biological discov- 

 eries upon medicine. In this way, also, will the example of Huxley be 

 most intelligible to us. I must here make a confession. When I tried 

 to ascertain how much time would be required to deliver my lecture as 

 I had prepared it, I found, to my regret, that its delivery would occupy 

 nearly double the time assigned to me. I had therefore to reduce it to 

 about half of its original dimensions. This could only be done by 

 means of very heroic cuts, seriously damaging in more than one place 

 my chain of ideas. 



The Beginnings of Biology. 



Huxley himself, though trained in the practical school of Charing 

 Cross Hospital, won his special title to fame in the dominion of biology. 

 As a matter of fact, at that time even the name of biology had not 

 come into general use. It was only recently that the idea of life itself 

 obtained its full significance. Even in the late Middle Ages it had not 

 sufficient strength to struggle through the veil of dogmatism into the 

 light. I am glad to be able to-day for the second time to credit the 

 English nation with the service of having made the first attempts to 

 define the nature and character of life. It was Francis Glisson who, 

 following expressly in the footsteps of Paracelsus, investigated the 

 principkim vitce. If he could not elucidate the nature of life, he at least 

 recognized its main characteristic. This is what he was the first to 

 describe as " irritability," the property on which the energy of living 

 matter depends. How great was the step from Paracelsus to Glisson 

 and, we may continue, from Glisson to Hunter ! According to Para- 

 celsus life was the work of the special spirit us, which set material sub- 

 stance in action, like a machine; for Glisson, matter itself was the 

 principium energeticum. Unfortunately, he did not confine this dic- 

 tum to living substances only, but applied it to substance in general, to 

 all matter. It was Hunter who first announced the specific nature of 

 living matter as contrasted with nonliving, and he was led to place a 

 materia vita diffusa at the head of his physiological and pathological 

 views. According to the teaching of Hewson and Hunter, the blood 



