In many cases of fever, however, there is no poison in the blood; thus, the local irritation of a boil or other inflammation may cause what is well termed "irritative fever." The way in which this is produced is by an indirect, and not a direct, action upon the inhibitory heat-centre.

The casualties of the late war proved but too abundantly that a man may be wounded in one part of the body and suffer from paralysis of voluntary motion in another part. Thus, a soldier struck in the neck fell unconscious, and on awaking was astonished to find his right arm powerless at his side. This is the so-called "reflex paralysis." Very commonly the irritation of a nerve will give rise to an impulse which will travel up the nerve to a motor-centre, and so excite it that it shall send in turn an impulse down a second nerve to a distant muscle, and a spasm result. Sometimes, however, the impulse which travels to the nerve-centre is of such a character that, instead of exciting it to action, it deprives it of the power of action. In the former instance reflex motion, in the latter reflex paralysis, results.

We have seen that galvanization of a nerve may excite the inhibitory centre to activity, and the peculiar persistent irritation of a local inflammation may deprive the same centre of its power of action: in the one instance a reflex inhibitory heat-centre spasm—i.e., lowering of temperature—is produced, and in the other a reflex inhibitory heat-centre paralysis—i.e., fever—results.

It would be going too far at present to assert that all fever is produced in the way spoken of. There are certain drugs which lower the temperature in the fever that follows division of the cord and consequent paralysis of the heat-centre, and which must therefore act either upon the blood, or universally upon the tissues so as to diminish their-chemical movements. It is most probable, although not yet absolutely proved, that there are other substances which act directly upon the blood and tissues in such a way as to increase their chemical activities, and thereby cause fever.

The practical considerations in regard to the treatment of disease which naturally flow from the recent investigations of fever are very important and very obvious. This is especially true since it has been shown in Germany that under the influence of a continuous high bodily temperature, not intense enough at any time to compromise life, all the muscular tissues of the body undergo a peculiar granular degeneration. Many a typhoid-fever patient has undoubtedly died from the heart-muscle having undergone this change, when, if by artificial cooling the temperature of the body had been kept down, the alteration of the heart-structure would have been prevented, and death averted. It is obvious, also, that the old plan of thwarting the intentions of Nature, and depriving the fever-patient of the free use of cooling drinks, was practically a baneful cruelty. As the body is burning up in fever, it is also evident that to deprive it of sustenance is to aid in the production of fatal exhaustion. The burning will go on, whether food is given or not, so long as the tissues can serve as fuel. Of course no more food should be taken than the patient can digest, but every grain of digested food is so much added to the resources of the system, which is engaged, it may be, in a close and doubtful conflict with disease.

If it were possible, of course the best treatment for fever would be that which lessened the production of heat. Fortunately, we have some drugs—notably, quinine and alcohol—which do exert a decided influence upon the vital chemical movements, but, unfortunately, their power is limited. As we are therefore often unable to control heat-production, the best we can do is to abstract the caloric from the body whenever it becomes so excessive as to threaten serious results. To do this, all that is necessary is to put the patient in a cold bath, or wrap him in a sheet wet with ice-cold water, or lay him upon an ice-mattress, or surround him with coils of tubing through which cold water runs, or use some similar efficacious device. I do not wish to be misunderstood. External cold is not to be lightly employed: it is a powerful two-edged weapon, capable of cutting both ways—a weapon as injurious and destructive in the hands of the ignorant and inexperienced as it is efficient in the hands of those to whom study and experience have taught its skillful use.

To illustrate what cold water may effect when employed by intelligent and skillful physicians, I may be permitted to cite a few hospital statistics from Germany and Switzerland, the only countries where the so-called antipyretic treatment of continued fever has been efficiently carried out on a large scale. From 1850 to 1861 there were treated without cold water, at the hospital at Kiel, 330 cases of typhoid fever, with 51 deaths—a mortality of about 15-1/2 per cent.; from 1863 to 1866, 160 cases were treated with cold baths, with 5 deaths—a mortality of only 3-1/10 per cent. In the hospital of Bâle, from 1843 to 1864, there were 1718 cases without antipyretic treatment, with 469 deaths—a mortality of about 27-1/2 per cent; from September, 1866, to 1873, 1121 cases were treated antipyretically, with 92 deaths—a mortality of a little over 8 per cent. Assuredly, we may claim that this water-treatment in typhoid fever is one of the greatest gains of modern medicine since the discovery of anæsthesia.

Some of my readers may here say to themselves, "Why, this is hydropathy!" Not so. It is the legitimate, not the illegitimate, use of cold water. It is the use of it as a single weapon, not as the only weapon of the armory. It is the employment of it in a single affection, not as a cure for all diseases.

Perhaps, in concluding this essay, I may be pardoned one word of counsel to my lay audience. Any physician who proclaims himself a follower of any special doctrine, be he a hydropath, an electropath, an allopath, a homoeopath, or any other path, should be viewed with suspicion. Water, cold, heat, electricity, drugs, are all agents capable of being used advantageously in the treatment of disease. Above all men, the physician ought to have that teachable spirit which is the offspring of true humility. Knowing the grave responsibilities which he assumes, living almost beneath the shadow of that past whose life-imperiling mistakes are so plainly visible in the light of the present, he, of all men, should be ever seeking for new knowledge, gathering with equal zest the seeds of healing in the waste as well as in the cultivated places, amongst the lowest and most ignorant of the populace, as well as in far-famed schools of medicine.

H.C. WOOD, JR., M.D.