"I show you too a specimen of heart muscle, in which the granular degeneration, or cloudy swelling is well marked whilst here and there the process is going on to fatty degeneration, similar to that seen in the kidney. Here again, then, the active elements of the organ are becoming broken down, or, at any rate, losing their normal structure and affording evidence of fundamental changes in these cells. Such changes are set up, not by any one poison alone, or by any single disease toxin, but by members of many groups of poisons, by alcohols, ethers, etc. indeed by very various poisons--animal, vegetable and mineral. "Now, it is a peculiar fact, as shown by Massart, Bordet and others, in researches on chemiotaxis, that nearly all these poisons have the power of repelling leucocytes, and of seriously interfering with them in the performance of their functions, and this power assumes a special significance in connection with our subject this afternoon. "Now, two of the great functions of leucocytes under ordinary conditions are those of policing and scavenging. Massart and Bordet showed, under the action of certain substances, alcohol amongst others, these functions are lost, but following up Metchnikoff and others they observed that after a time these same leucocytes became accustomed to the presence of these poisons, gradually becoming 'acclimatized' as it were. At first paralyzed or repelled, they after a time pluck up courage to attack the invading substances and carry on or renew their accustomed work of scavenging; they try to get rid of both poisons and poison-producers, and even acquire the power of forming substances (anti-toxins) which can neutralize the poison and allow the cells to devote their energy to doing their own proper work.