The idea that children must have measles and whooping cough is an entire mistake. If these diseases do not kill children directly, they kill a very large number indirectly, and maim a great many more by leaving them liable to diseases of the respiratory organs ; hence, if possible, children should be prevented from catching them. Many people will allow their children to take measles. I consider that they are wrong, and that they ought not deliberately to expose their children to that which may kill them ; they have no business to assume that their children will get that disease, and must have it, and I am sure no child has ever been the better for having had it, while many are injured for life.

Now, all these diseases spread more where there is overcrowding, and so they always spread in large towns. You can understand, from the various ways in which these diseases spread, that they are more dangerous where people are crowded together, but this is especially true of typhus fever, which is only at home in very crowded parts of towns. It does not spread in other parts if it is introduced, and in fact the infective distance of typhus fever is very small Although it is an extremely infectious fever it does not spread from one spot to another, through persons going occasionally to see the patient, nor does it attack the attendants if they do not handle the patient. It is a fever that was formerly known as jail fever, and was given other names, according to the overcrowded places in which it spread, and it is one of the diseases of which we are told that the poison can originate spontaneously.

We have been gradually reducing the number of diseases of which we believe the poison originates spontaneously. Now, typhoid, or enteric fever, has only been recently separated from typhus fever. It has been shown clearly that whereas typhus fever spreads especially in overcrowded places, and among the poor and destitute and starved, typhoid fever spreads, on the contrary, wherever the matters that are discharged from the intestines of human beings are not got rid of from houses or towns. The distinctive characteristics of these two diseases I will not enter upon, but they are so different that it is a perfect mystery to us now that they should ever have been confused. We have seen, too, the different ways in which these diseases spread.

We are told on very-high authority that the poison of enteric fever is capable of originating de novo in filth of various kinds, that you only have to have a certain amount of decomposing matter, under certain circumstances, and the poison of this disease can be produced and given to human beings. This statement is supported, too, by the assertion that in the majority of instances where cases of typhoid fever arise you are not able to find where it came from. Now, with regard to that, I would point out to you that it is a disease a person may suffer from for weeks, and with which he may go about from place to place without knowing that he has it. A person may go through it to the third stage, and then fall down dead with it, and the disease may he regarded as heart disease. Now, notice that wherever he has gone for the last three weeks he has been spreading the poison of typhoid fever.

These are a few facts which show you that it is a ridiculous impossibility to expect that we can trace the poison of this disease always to the place from whence it came. It may be mixed with milk in the Midland counties of England, sent up to London, and distributed to a number of houses in Londoa The connection between these may never be known, and there is no doubt that that method was never suspected until the recent epidemics of thitf disease occurred; and I put it to you whether we are in a position to say that we are able in a case of this disease to state that the poison was not derived from a previous case.

We are told also that this disease is not generally communicable from one person to another, because it is frequently taken to a place, and does not spread there ; the answer to that is perfectly clear,-in those places precautions are taken to remove matters containing the poison. Smallpox, scarlet fever, and typhus fever, do not spread if proper precautions are taken, and that is why typhus fever does not spread in the West End of London, although it is taken there over and over again.

We can also bring forward arguments of another kind; we can point to places where filth has been accumulating for years, places, you would say, most suitable for cholera and enteric fever, if the poisons of these diseases are developed in decomposing animal matters, and yet these diseases have not been there for years; the answer to that is, that all the conditions are not present Now, on a certain day a person comes to one of these places ill with enteric fever, they do not know what is the matter with him, and he is attended, perhaps, for a week or two. As soon as they have found out what is the matter with him, a score or so of persons have already become infected with the fever, and it spreads over the place like wildfire. This shows you that the place was in an admirable condition for the poison of that disease to spread if it could have originated there, and though you may come to the conclusion that the disease was not there before because there was some missing condition, you must admit that the person who came there ill brought the poison.

I will now tell you a few practical methods to prevent the spread of these diseases.

The first method is by separating persons who are sick from the healthy community; that is the method pointed out by Moses in the 13th and 14th chapters of Leviticus, two of the most admirable sanitary chapters that have ever been written. One form of leprosy was undoubtedly an infectious disease, which some people have said was smallpox.

The sick people are to be separated, and so it is necessary to have fever hospitals. Mind these diseases do not spread from fever hospitals. There is no instance known of any of these diseases having spread from the London fever hospitals to houses in the neighbourhood, yet it is true that sometimes these diseases are found in some of the houses in the neighbourhood, and especially in public-houses where they have been conveyed by the attendants; but there is, at any rate, not sufficient need to have the great amount of fear that people seem to have on this subject.