THE BATTLE OP THE MICROBES.

Evening Star, Issue 10411, 4 September 1897, Page 1 (Supplement)

THE BATTLE OP THE MICROBES.

•The following is the conclusion of Mr Mellor’e address to the Sanitary Institute AICOnOIi-MAKIKG MICROBES. Alcohol you may be acquainted with. . The gas is that which, forcing its way through the dough, makes the bread “ rise,” The same gas is given out hy us every time we exhale a breath. You mutt be very familiar with these microbe?, for when I toll you that if yon have a bucket of yeast you have a bucket of these sugar-eating a'cohol-making microbes. u We know too well what an attraction alcohol has for some men. But there is a microbe that has this human appetite for alcohol in a far greater degree than the most cmfirmed dipsomaniac. In alcoholic liquids this microbe lives and muldplies. It consumes the alcohol and manufactures acetic ac d. If the alcohol is in the form of beer then vinegar results. This micrJba only realises itself iu a cask of beer, and if P; oliibitioni-ts could only hear tho microbe’s feeble wail for food they might think twice before condemning it to starvation,” But this vinegar-making microbe shows greater wisdom than man, for it will have nothing to do with fluids containing over 10 per cent, of alcohol. Hence, it will take nothing stronger than porter, ale, our temperance hop and herbal beers, stout, gooseberry wine, and such like, Next time you have peas, beaus, or any such like leguminous plant in your garden just go and pull one—a healthy one —up by the roots. On washing it under the tap you will notice small white nodules on the roots, -these hj t tie knobs are of ten full of microbes. Thi-j----help the pea togot the nitrogen it requires from tho air. If there vrere none tho pea plant would be a sorry object indeed This is remarkable: the pea plant can only grow in abundance when it is assisted by these microbes. Again, there is reason for believing that if we were not assisted by the microbes, we too, like the pea or bean plant, would be next door to starvation. The , microbes which we must of neo ssity swallow with our food help the digestive system in getting the nutrition from tho food. This means that if wo could prevent all the bacteria from getting into our body wo should be unable to extract that amount of nutrition from our food which the body requires. It may even be possible that sometimes indigestion is caused by a a.~amty of microbes in the alimentary canal. Therefore a goo 1 stock of microbes in our system is not altogether an evil, presuming, of course, that the microbes aro not those that produce diseases. This is comforting in more senses than one. For instance, in l-.issing an interchange of microbes might occur which could possibly proyo of great value. This was first pointed out by Dr Bridger, and 1 am sure he will win the heart of every lad and lassie in the romantic world. The mutual assimilation of the nectar of beautiful lips may doubtless now be placed in the category of those necessary to human happiness and health. It will be tound a popular remedy lor dyspepsia and indigestion. We have microbe nursjries for cultivating varieties which impart special flavors to wines. Microbes for butt°r and cheese making. But I cannot dwell longer on those microbes so useful in helping us to run “ this mortal coll” with pleasure and happ’ness. You will remember 11 Id youthatmeats, fruits, aid such like are preserved from putrefaction by so tinning them that no microbes are present in fc# tin. Suppose by a little citelessness in the canning that microbes, dining en that sort of stuff, remain is the can unbilled. They set to work and make, not alcohol, not vinegar, but ptomaines or poi«onr; amd some of these are fearful poisons indeed. This accounts for those cases, which are unfortunately not uncommon, where whole families have been poisoned after partaking of tinned meat or fish, as well as the complaints recently made in England against colonial frozen meat. The ptomaines were there, showing the microbes had been living actively. Some ports of microbes, when they get into our bodies, also set to work and make poisons, each poison according to the kind'of microbe present. Just as phosphorus causes frightful agony before it kills, or laudanum lulls us into a gentle slumber, so each particular poison has its own peculiar action. 'I he effects of one poison sre known as the symptoms of or the disease of typhoid fever—another measles, influenza, whooping cough, and so on with some thirty others. 'J he products of the action of microbes can often be separated from the microbes producing it, and these poisons when introduced into tho system produce effects somewhat similar to that produced by the microbe. Therefore the introduction of these malignant germs into the system not only resembles the introduction of such a poison as strychnine, but also resembles tho introduction of “a poison manufacturing apparatus, together with a machine capable of making other machines capable of making poisons.” Before I explain what occurs in the system when mio'obcs are introduced I must briefly describe certain elements in our body. It docs not require much manipulation to show that fresh blooi is a colorless fluid in which a great number of red and white bodies float. On standing the red, round bodies arrange themselves end to end like a great pile of shillings, while tho liquid plasma separates into a solid and a liquid portion called the serum.

Bodies Leucocytes Blood \ 1 Bed Bodies .Red Corpuscles [Liquid, on standing We are only concerned to-night with the white bodies and the serum. The little white masses which are also found in many parts of the body, though principally in the bloodvessels, have the power of going through the walls of the bloodvessels, and are capable of wandering all over the body. If a drop of blood be placed under the microscope, by taking suitable precautions two or three of these things are almost sure to be there. If alive, its shape is constantly changing. It has the power of sending out little bits of processes which seem to got a grip of the floor, as it were, and then the rest of the j lly is drawn up, Again these little feet, if we might so name them, are sent out, and again the body is drawn up. This being repeated again and again, the piece of jelly o awls about. Instead of jelly drops or gam specks they are called by the name LEUCOCYTES, • which means “ white cells.” It seems strange for these leucocytes to be crawling up and down over our system, not only in the bloodvessels, but also among the tissues of our body. What uso are they to us? They live by absorbing nutrition from the blood ; and some will say surely they are parasites and would bs better away. Supp. se a very small bit of potato be near the leucocyte we have under the microscope. It seems to know there is something good to eat about. Out go the little feet, and soon the leucocyte is alongside; now the feet gradually embrace the potato. But since it is more usual to embrace with the arms, perhaps I should say gradually embracing the bit of potato in its littU arms the leuoooyts soon surrounds the potato, and now a bit of potato is seen as it inside a speck of jelly. By-and-bye the leucocyte sends out little feet and flows away, leaving behind the bit of potato. But just as a dog takes all the meat off a bone, and leaves behind the bone which it cannot digest, so the leucocyte has taken from the potato the protoplasm which it can digest, and it leaves behind the rest. Thus, besides leucocytes or white cells, these specks of living jelly are sometimes called “ eating cells,” or phagocytes. You may meet with either of these names in the course of yonr reading, and that is the reason for my mentioning them. There are millions of these strange things in our system, and there is reason for believing that the spleen, a little organ near the stomach, is almost exclusively used in making them. How the leucocyte knows when something good to eat is near I don’t know. I do know that if I go past a house where “steak and onions " are being operated on my nose makes iriy stomach say “I’d like to be there.” But the leucocyte has no nose, no eyes, no mouth, no anything other than a shapeless mass of an ever-changing, jelly-like substance, called protoplasm. Still the leuo-cvte does know when anything good to eat is near. “ When it wants an arm or a foot it thrusts out a part of the jelly. When the arm or foot has served its purpose it is absorbed into the rest of the jelly. Now the jelly acts as a stomach, 9 he _ leucocyte is then nothing but stoinach. Having digested its food the leucocyte again becomes the simple speck of jolly, ready, should occasion arise, to make an impromptu arm cr foot, or to extemporise a stomach.” Again, I ask, what usa are these strange bits of living jelly in our system ? What have leucocytes to do with microbes ? It anything gets into our system that does not belong there the leucocytes try to eat it. Fumbling about a gooseberry bush in the /summer time a thorn not uncommonly sticks in the finger. If you leave it the flesh soon swells up and a yellowish white creamy matter collects. The swelling is caused by the leucocytes rushing from all parts of the body, crowding round the thorn expecting a feed. The yellowish matter is full of leucocytes. They cannot eat the thorn, otherwise they would; the inflammation would cease, for the leucocytes would again scatter themselves. Similarly, when any microbes enter the system the leucocytes rush straight at them, hoping for a supper. This the microbes try to resist. A PITCHED BATTLE often results. Now you understand the answers to the two questions I propounded. On the one band, the leucocytes act as scavengers of tho system, while with the microbes it is war—a fight with no quarter. We hear no thunder of explosive •torpedoes, no booming cannon, no rattle of musketry, no clash of arms, no shouts of victory. None the less earnestly the battle is waging. The battlefield, is our body ; the invading army is the microbes; the defenders are those little specks of living jelly, the leucocytes. The weapons used by the microbes are the deadly

poisons they are able to manufacture, and which are carried round the system by our blood vessels. These poisons, I say, together with their power of multiplying with such extraordinary rapidity as I have pointed out, are the weapons of the microbes. The leucocytes fight with their stomachs and enormous appetites • and what an appetite they have, to be sure! iometimea, indeed, they are more microbe than leucocyte. 'Directly a microbe enters our body it commences to breed at a fabulous rate, and at the same time the increasing numbers manufacture poisons, deadly and subtle, iu constantly increasing quantities. Simultaneously with the appearance of the invading microbe on the field of battle, the leucocytes, acting, as it were, like sentinels, spread an alarm. Instantly the leucocytes rush to the place' of invasion. Each leucocyte, becoming a big stomach, engulphs numbers of microbes. Slight skirmishes are constantly going on—now, it may be, iu my body, now in yours. By-and-bye we feel seedy, then we have tho symptoms of disease. If the battle is keenly contested we have a severe attack. If victory rests with the microbes we die; but if the leucocytes win we are again restored to health and strength. If we are tohavo health tho leucocytes must win. Therefore, in order to be strong and vigorous, it is necessary that our leucocytes be in good order. It is only when the body is in a low state by over-exertion and such-like that the leucocytes are w.ak, and then the microbes have a better chance of victory. When the holy is fresh and vigorous the microbes have little chance of victory; but there are some exceptions to which I shall eoou refer. Remembering how widely the microbes aro scattered about, we hare nofc much chance ** to shut the door and keep the germs out ”; but I think we can at any rate keep the body in good form, and so ensure healthy and good fighting leucocytes. I am reminded that the late M. Fasteur was one day at dease;t eating fruit. He was most careful to wash tho skin of each cherry or grape before eating it. Enlarging on the possible evils that might arise from the spores of direases sticking to the skin of the fruit, the eminent scientist got warmed up with his subject, and, putting the tumbler to his lips, unconsciously drank off the water into which he had wa~hed all the microbes. I beard of no ill effects from the botanical garden he had swallowed. There are SOME EXC BPTIONAL MICROBES against which the leucocytes do not know how to fight. There are even some from which the leucocytes would rather run than fight. If these varieties of microbes enter the system, victory rests with the best fighter, the microbe. Where the leucocytes make some stand the battle is always severe, and the battlefield, when the fight is over, is seered and scarred with the effects of the fight. Smallpox is of this kind. V/ith those microbes to which the leucocytes show the white feather the fight is soon over, and a “ funeral march to the grave ” ends all. Some microbes on entering tho system form a sort of mass too big forthe leucocyte to swallow. The poison manufactured acts very slowly, or the poison is not so deadly as the disintegration of tissue— e.g„ leprosy. Then the spread of the disease is slow, but sure.' The bottle is long, but certain victory awaits the invaders. In 1884- a criminal in Hongkong preferred being innoculated with leprosy “ virus” rather than be hanged. I recently noted an account of his death. In those cases where the leucocytes are poor fighters it would certainly bo to our advantage if we could train them to fight. A little consideration of certain facts in the light of that which I have said will point out the way. Wo know that the action of the poisons manufactured by microbes in many oases closely resembles the action of the venom from poisonous snakes. The natives of South Africa believe, so the travellers tell us, that if a man be bitten by a poisonous snake, and recovers after he has shown marked symptoms of poisoning, then he has no need to alarm himself if-bitten subsequently. Everyone is familiar with the fact that one attack of many of the infectious diseases gives the body power to resist further attacks. For instance, oneattack of measles generally protects for a lifetime ; so, too, with scarlet fever and smallpox. Again, some persons are insusceptible to certain diseases by their own peculiar constitution or idiosyncrasy- Similarly, many animals cannot take certain diseases— e.g., mice cannot take diphtheria. This power of resisting a disease is called '

IMMUNITY, And the animal is said to be iiiimune. Sometimes the immunity is not absolute, but only occurs under certain conditions. Amphibians aud most birds, in their normal state, cannot fake anthrax. But we know two important facts;

1. Anthrax microbes can only thrive between IGdeg and 45deg C. 2. The blood of birds is hotter than 45deg, while ;ho blood of amphibians is below IGdeg.,

On trying an obvious experiment it was observed that by reducing tho temperature of the Wood of, say, a fowl, or raising the temperature of the blood of a frog, the bird and frog are no longer immune, for they are now susceptible to the disease. Hence birds and amphibians cannot tako tho disease while they are in their normal state, because - tha temperature of their blood is unsuited for the growth of the microbes. Immunity may be na f ural or artificial. The immunity of birds to anthrax is natural, because in its normal state a bird cannot take the disease. Protection from a disease induced in other ways is known as artificial immunitv. When we observe tho symptoms of an attack of microbes, if we knew the conditions under which the leucocytes have the best chance of fighting the invaders, it is to our advantage to give the leucocytes that benefit. To • day there is a band ‘of earnest and devoted students working with all their energies seeking to discover means of inducing artificial immunity and to help us the better to combat the ravages of these hostile microbes. It is noted that an animal suffering with tuberculosis hue *ar more chance of recovery if it is espocCd to plenty of sunshine; whereas, if an animal Buffering from cholera or typhoid bo exposed to sunshine it is far more likely to die. Hence it is clearly to the advantage of consumptive patients to live in sunny places, while there is an uncomfortable uncertainty of the wisdom of basking in tha sunshine for patients affected with typhoid and cholera. Hence, too, we find an explanation for the greater prevalence of typhoid and cholera in those countries where the sun shines with greater power and more continuously. But there are other means for securing ARTIFICIAL IMMUNITY. I will explain the method of attenuated or weakened cultures, and as an example, typical of others, I will use Pasteur’s method for hydrophobia or rabies:—

1. Microbes may be bred artificially on gelatine, and generally in a few generations the microbes become so altered that microbes previously deadly are now harmless. This fact is of some interest to evolutionists.

2. It is known that by inoculating the virus of hydrophobia from dogs into rabbits the microbes become even more deadly. By inoculating from dogs into monkeys the microbes become less deadly.

3. Again, it is known that the virus of hydrophobia gradually loses its strength when kept, and in fifteen days it loses its deadly character altogether. Therefore the virus while fresh is strongest and that fifteen diys old is the weakest. 4. It is also noted that the virus of hydrophobia seams .to lie in the central nervous system, i.e., the brain and spinal cord.

So that if it be desired a virus of any degree of strength can be obtained by keeping the brain and spinal cord a suitable length of time. To combat the ravages of the rabian or hydrophobian microbes the Pasteur Institute proceed approximately as follows: A mad dog is killed, its brain and spinal cord removed. This, when beaten to a paste, is diluted with broth. It is then known as the virus of hydrophobia. A rabbit is next stretched on the dissectieg board and chloroformed. A little disc of bone is removed from its skull and two drops of the diluted virus, prepared as I have just shown, are injected beneath the skin covering the brain. The wound is properly dressed and allowed to heal. In time the rabbit dies of hydrophobia. Its brain is treated in a similar manner to that of the dog, and then injected into another rabbit. This repeated again and again gives a virus which gradually becomes stronger and stronger. When a virus is obtained of full strength the brain and nerve system is preserved in a bottle, when its strength gradually becomes weaker and weaker. After fourteen days it is inert and has no effect, and maynow be thrown away. By having a rabbit dying every day tho Pasteur Institute always have on hand a stock of viruses of known vary ingstrengths. If a person bitten by a mad dog goes to the Pasteur Institute the whakost virus of all is injected into him. On each succeeding day virus of a gradually- increasing strength is injected until on the fourteenth day -the most powerful virus is used. After this the patient rarely dies from rabies. What is happening? When a person is bitten by a mad dog the germs left by the dog’s saliva take about five weeks before they begin to affect the person seriously. This is the period of incubation. But in- tho meantime the weak dose of active vi ns is introduced. This may be easily conquered by the leucocytes. By succeeding doses of increasing strength the digestive powers of the leucocytes are trained and increased. AVhen trained the leucocytes can overcome a strong dose which, if given to them suddenly, would paralyse them, because unaccustomed to it. Then the microbes would have the fight all to themselves. The leucocytes have been trained in the interval between the bite of the dog and the development of the microbes. The trained leucocytes can now easily- overcome them. Thus a disease, at one time deadly to a certainty, ia now deadly no longer. But what is this injection and inoculation I have been speaking about ? . When, the injection is done with the virus of smallpox we call it

• ■VACOWATION. ' Vaccination then trains the leucocytes iu oar

blood system to fight the microbes causing smallpox. Suppose there are other microbes present in the . vims used for the inooui v on ,° e - 3^e3 ' those .of smallpox, then, although smallpox may be prevented, other di'cases, perhaps worse, may be given to the patient. The anti-vaccinationists in reality do nob cry against vaccination, but against careless vaccination. Carelessly prepared, the vaccine may become a disease-carrying not a diseasemodifying agent. -Is it an application of the principle like cures like ”? Just as many require to eat a dozen or so tomatoes before they can eat them with pleasure, so you must give your-leucocytes a few of the particular kind of microbes before they can be eaten without evil effects. lam not very, fond of quoting statisfr Vh “ Bt *«stics are great liars. The truth is, I think, that they often tell ns more than wo understand. The ‘British Journal recently published the followmg table as the

MORTALITY RATE FOR SMALLPOX PER MILLION OF PEOPLE.

Of course wo have to allow for improved sanitary conditions, greater knowledge in arts of preventing diseases. Still, taking Austria atd Belgium, as well as Spain and Germany, in pairs, the figures seem to bo significant. There are, however, other views regarding the action of the inoculation of the attenuated or weakened virus in securing immunity, and, as is very often the case with rival theories, there is something of truth in each, though at the present time it is in the throes of disputation. I, will mention the important ones. IVoodhead and Wood think that by gradually increasing the strength of the virus the leucocytes become accustomed to the poisons, and can then carry on their work undisturbed even when the microbes are in full force, the microbes being then treated as a foreign body, and destroyed in the way I have previously shown; whereas, if the leucocytes be suddenly attacked by a strong dose of virus they are paralysed, and the microbes can sot to and manufacture poisons without hindrance. Here the aotion seems to be similar to that by which many have accustomed themselves to such poisons as arsenic or morphia in quantities so large that they would at once kill one unaccustomed to them. The inexperienced tyro learns to his dismay the sad havoc the use of the fragrant weed may make with his untrained digestive apparatus. “My lady Nicotine,” though apparently not unkind to habitual worshippers, makes a sorry object of the uninitiated. Pasteur used to think that by inoculation or vaccination, or a first attack of a disease, the germs devoured all the food, and when any subsequent bacteria got into the system, there being no food, starvation resulted. Klein and Klebs hold the view that some chemical product.is left behind by the microbes first in the field, and in whioh those coming in later on cannot thrive. This product stays in the body a long time. As long as this product or ptomaine or poison remains in the body no microbes can live there. I might illustrate this by supposing a burning candle to bo a living microbe, and a candle not burning to be a dead one. When burning in a jar there is a product being formed which acts as a poison to the Jiving candle. By-and-bje the candle is put out by its own poison, and any other burning candle put in is a'so put out. The second burning candle represents a second attack of the microbe. Suppose, Row, we could get some of this poison made byTho first candle and put it in the jar, then we don’t need to have a burning candle at all, for no candle can live in the jar in the presence of that poison. [Experiment shown ] So, too, if we could get the poison made by a particular disease-pro-ducing microbe and inject it into the body the first attack of the disease would be unnecessary. No microbe ot that kind o»uld live in its presence. Thus, instead of inoculating with living microbes only, the poison manufac tured by the microbe is introduced. More recent work, however, seems to indicate that there is some change brought about in the serum of the blood whioh tends to neutralise or stultify the effect of the poisons or toxines produced by the microbes ; for not only can an animal be rendered immune from living microbes, but even against the poison of the microbes. And, besides, the blood of an animal whioh has been trained to withstand a particular disease is able to protect other animals from that disease. Possibly this resembles somewhat the aotion of the “ tuberculin ” of Koch, whioh is intended to prevent tuberculosis microbes from thriving. By a process which I have not time to explain the active principle or poison manufactured by the tuberculosis microbes is sep»rated, and is called TUBERCULIN. This “tuberculin” injected into animals suffering from tuberculosis to a certain extent resists the advance of the foe. The leucocytes or police whilo arresting the inarch of the disease germs are strengthened and are enabled to resist them, or else the poison made by the microbes is counteracted by the changes in the serum of the blood brought about by the antitoxic tuberculin. Speculations on the cause of immunity are of deep and vital interest. These meagre outlines must suffice for the present. We may summarise them as follows 1. Starvation (exhaustion of food). 2. Poisoning (retention ot poison in body inimical to the growth of succeeding invasions]). 3. Leucocytes being trained (<t) To fight the microbes, (W To withstand paralysing action of poison. .4. Changes in the serum of the blood acting either (а) Against the microbes themselves (antiruiorobic), (б) Or neutralising their poisons (anti-toxic). Tuberculosis is known by many names, according to the part of the body the microbes may attack. If in the lungs, it is called consumption; if in the lung covering, it is called pleurisy ; if in the intestino, it is called consumption of intestine ; if in the brain, it is called meningitis; if in the external parts, it is called scrofula. Something similar to the action of tuberculin is the now famous antitoxin for diphtheria. We can easily picture what occurs in diphtheria by a simple application of what I have already told you. A, child may encounter diphtheria germs every day and yet have no ill effects, because the child is in full health. Suppose. however, that the child has a simple cold, then a alight inflammation occurs. “The germs, previously inert, now encounter conditions more or less favorable for their growth. Now they settle on the child’s tender throat and develop with frightful rapidity, producing croup, then diphtheria, and possibly death." The action of tetanotoxin, the poisonous product of the bacillus of tetanus, produces lockjaw. This microbe is one of the most subtle and determined of our lowly foes. It is one of the most obstinate of our enemies. It lurks everywhere; it is very common in garden soils and stables. They can only gain access to man or animals through an abrasion or wound on the skin. They there multiply and produce poison in the usual way, which in turn sets up the peculiar nervous disorder lockjaw. Frankland quotes the case of a child cutting its finger while playing with the kitchen knife. The fond mother bound the bleeding wound with cobwebs—a stupid and superstitious practice. A month later the child developed symptoms of lockjaw. This is a true story, for some of the fame spider’s web was injected into rabbits, which died with tetanus symptoms. Thus was it proved beyond doubt that the disease in the child was due to the spider’s web, whioh had evidently served as a resting place for these cruel microbes until an opnortunity arrived for them to find a more suitable home.

Not many _ years ago the mortality amongst _ surgical practice was considerable owing to the secondary effects arising from this very disease. Since lockjaw was proved to be due to microbes, and knowing tow the air is laden with germs, the surgeons’ efforts were directed to preventing all contact between the wound and microbes. The microbes on all the instruments, the opera or’s hands, and the dressings of the wounds are killed by some germicide, say a dilute solution of carbolic acid. The instruments and dressings are then said to be sterilised. During the operation also a spray of this same carbolic acid plays over the wound, the hands of the operator, and over everything he touches. Thus there can be no living microbes near or on the wound, the result being that it is very seldom wo hear of this lockjaw, and operations previously impracticable cm now be successfully performed. This is the principle of what is known as Lister’s antiseptic surgery, which ha's revolutionised the methods for the treatment of wounds. It furnishes a brilliant application of the theory of microbes. As a rule exposure to sunlight and plenty of fresh air is fatal to microbes. Boiling in water generally kills them. The spores, on account of their protective envelope, are more resistant and require much more prolonged heating than the microbes themselves. Substances which kill or destroy microbes are germicides, bactericides, or disinfectants, while substances which simply retard or hinder their growth aro antiseptics. Generally an antiseptic is a dilute germicide, and vice versa, a germicide or disinfectant is a concentrated antiseptic. In the following table these substances are arranged in the approximate order of their activity 1, cremation ; 2, corrosive sublimate; 3, iodine; 4, bromine; 5, chlorine (chloride of lime); 6, sulphurous acid (burning sulphur); 7, salicylic acid; 8, carbolic acid; 9, baric acid; 10, alcohol; 11, encalyptol. Before concluding I will describe the

PA3TEUE-OHAMBEBLAND HICHOBE FILTER. 18 remarkably simple, very good, and perfect,. Its general appearance is like a candle, whence m France it is called bougie Chambertana -Chamberland’s candle. It is : o arranged raat it can be fixed on to an ordinary water tap. , t^ a ter flows from the water tap into a metallic receiver, inside which is a long cylinder made of unglazed porcelain or biscuitware, through the walls, of which the water from the metallic, cylinder is forced bv the pressure from the water tap. From this biscuitware cylinder the Altered water runs directly wherever desired. Not even the most minute organism found in. water can find its way through the biscuit - ware of the Pasteur • Chamberland filter, whereas with a ? - °™ , na ry filter of crushed sandstone, charcoal, very few microbes are arrested at all nay, the presence of the organic matter winch such filters do Arrest Bctuslly serves _-as a breeding ground for microbes [chamberland candles and the filter shown in action.] The candles should always be tested before use, as they are liable to be perforated here and there, with small holes, quite large enough to admit the passage of microbes. But I must conclude. The stupendous importance of my message to-night Is, I hope, sufficiently clear. The m’erobe theory c:n walk without crutches, being now a science of positive fact. Increasing knowledge is sweepingdown the accumulated cobwebs of indifference. Many details of the theory may be modified or altered as tune goes on, yet the ma : n features of the framewoik or skeleton I have presented will remain, because it is built on a rational interpretation of solid facts.

o,Ki? n y °j ter^? y l s * ssue tb® word “streptococcus appeared as f strepococcus.”j Limelight illustrations were given from a lantern manipulated by Mr W. H. Scott. At the close of the lecture Dr Ooston said that Mr Mellor had touched on a subject which some of them might yet enlarge upon, or possibly Mr Mellor himself. The attend-ance-showed that the subject was a popular one, and he hoped they would be able to set up snob a lecture again, and thus popularise the Sanitary Institute. He moved a vote of thanks to the lecturer for his able and instructive address, which was carried by acclamation.

Last Century. Permissive Vaccination. Compulsory Vaccination. England . 2,000 417 53 Sweden 2,(145 4S0 Prussia .. 2,000 309 Italy — 440 110 f Austria _ 5S0 l Belgium .. — 441/ /Spain /Germany .. 1.ROO is}