116 III. NON-ELEMENTALISTIC STRUCTURES
capable of altering the colloidal structure of the living protoplasm must have a marked effect on the behaviour and welfare of the organism.
Experiments show that there are four main factors which are able to disturb the colloidal equilibrium: (1) Physical, as, for instance, X-rays, radium, light, ultra-violet rays, cathode rays.; (2) Mechanical, such as friction, puncture.; (3) Chemical, such as tar, paraffin, arsenic.; and, finally, (4) Biological, such as microbes, parasites, spermatozoa,. In man, another (fifth) potent factor; namely, the semantic reactions, enters, but about this factor, I shall speak later.
For our purpose, the effects produced by the physical factors, because obviously structural, are of main interest, and we shall, therefore, summarize some of the experimental structural results. Electrical currents of different strength and duration, as well as acids of different concentration, or addition of metallic salts, which produce marked acidity, usually coagulate the protoplasm, these effects being structurally interrelated. Slow coagulation involves changes in viscosity, all of which, under certain conditions, may be reversible." When cells are active, their fluidity often changes in a sharp and rapid manner.4
Fat solvents are called surface-active materials; when diluted, they decrease protoplasmic viscosity; but more concentrated solutions produce increased viscosity or coagulation.5 The anaesthetics, which always are fat solvents and surface-active materials, are very instructive in their action for our purpose, as they affect very diversified types of protoplasm similarly, this similarity of action being due to the similarity of colloidal structure. Thus, ether of equal concentration will make a man unconscious, will prevent the movement of a fish and the wriggling of a worm, or stop the activity of a plant cell, without permanently injuring the cells.8 In fact, the action of all drugs is based on their effect upon the colloidal equilibrium, without which action a drug would not be effective. It is well known that various acids or alkalis always change the electrical resistance of the protoplasm.7
The working of the organism involves mostly a structural and very important 'vicious circle', which makes the character of colloidal changes non-additive. If, for instance, the heart, for any reason, slows down the circulation, this produces an accumulation of carbonic acid in the blood, which again increases the viscosity of the blood and so throws more work on the already weakened heart.8 Under such structural conditions, the results may accumulate very rapidly, even at a rate which can be expressed as an exponential function of higher degree.
Different regions of the organism have different charges; but, in the main, an injured, or excited, or cooler part is electro-negative (which