(3) As a practical result of this a daily excretion of uric acid amounting on meat and tea diet to, say, 20 grains, can in eighteen months to two years be reduced to 10 or 11 grains a day; and with this reduction the diseases due to uric acid gradually diminish and cease to trouble.

(4) This result has nothing whatever to do with individual constitution, age, digestion, or metabolism; it is simply a matter of swallowing or not swallowing some 8, 10, or 12 grains of uric acid each day.

(5) Quantity of food on a diet on which one has lived from childhood is a matter of habit: one unconsciously learns as a habit to eat enough ; but even here one may learn to eat too much. On a new diet one must have some rule to prevent any serious mistakes; but no rule is absolute, it is a rough guide to be adjusted by each individual. The rule of 9 or 10 grains of albumen per pound of body weight per day is the one that was taught in all text-books of physiology when I was a student twenty-five years ago. These twenty-five years of use have not enabled me to convict it of serious error; on the contrary, I believe that for a rough guide it is very close to the truth, and that investigation would show that when the weight to be nourished has been properly calculated (and this, of course, requires skill and experience), there are not many people who do good work in the world and maintain their weight, strength, activity and blood colour at the normal standard, on less than 9 grains of albumen per pound of body weight per day.

(6) No one has, I believe, found any xanthin or uric acid in milk or cheese, and the taking of one and a half pint of milk and one ounce of cheese every day does not interfere with the reduction of uric acid from 21 grains down to 10 per day (see No. 3). Some German chemists, on the other hand, have found xanthin in the yolk of eggs, and the taking of eggs does at once raise the uric acid above 10 grains per day in proportion to the quantity of egg taken. Milk and cheese are therefore uric-acid-free foods : yolk of egg is not. Thus far we have nothing to do with individuals, all are absolutely alike; those who swallow uric acid suffer from its effects, those who do not swallow it do not suffer.

(7) But when we come to deal with the available uric-acid-free foods, it is quite a different matter: here every individuality in health, disease, deformity, age, and condition has to be considered in deciding which foods offer special advantages for each individual case; and here there is scope for endless experience and discussion, which I shall not attempt even to outline in a letter.

I can now, however, indicate shortly what I should say in reply to your friend's remarks. As to milk and cheese, I know some who do best on large quantities of milk, and I know others who do best on none ; such fluid diet is very bad for some diseases, very good for others; there can be no rule for all. The harm that Cantani saw in gout and rheumatism from taking milk and cheese was possibly due to taking them in excessive quantity, or to the acids and salts in cheese, or to the dyspepsia which is in some people produced by milk ; but gout and rheumatism are but a small part of the diseases produced by uric acid; and the harm that milk and cheese did in these was not due to introduction of uric acid. I have known cheese cause a relapse of rheumatism; but this was because it contained much salt. I often purposely put patients on too large an allowance of albumens at first as in some diseases it is safer to be overfed rather than underfed ; and later, when the patient has got over the change of diet, the quantity can be reduced.

As I say in "Diet and Food," but few people want more than 1,400 grains per day; but it is easy to over-estimate the exercise taken, and also to over-estimate the correct weight, or proper quantities of tissues to be nourished, as distinguished from fat which does not want extra nourishment. No doubt I often make mistakes in these matters in spite of my best endeavours. No rule is or can be absolute which has to take such data into account. If strength and blood-colour keep normal, I am content no matter how little food is being taken; but for those who maintain strength and colour over years my figures will not often be found to be very far out.

I do not know anything about Cantani's metabolism.

I do know that, if I do not swallow uric acid or take too much food - i.e. above the 9 grains limit (an error which may be committed on all diets) - I do not suffer. I quite agree that each person is to some extent a law to himself, especially as regards digestion; and to a lesser extent as to quantity; but the great physiological law of quantity is much less often broken than might be imagined. As to kinds of food each must try for himself, only general rules can be stated, and your friend is quite right in saying that the mistakes of individuals in details do not affect the great principle of the exclusion of uric acid. I am also inclined to agree with him that constipation is often a question of finding the particular uric-acid-free foods that suit the individual in question. Still even here it is a rule that milk and cheese are constipating (and this may account for part of their evil influence in gout and rheumatism as noticed by Cantani), while some breadstuffs and most vegetables and fruits have the opposite effect. Constipation may precipitate an attack of gout or rheumatism, but it does not cause it; and it can only precipitate it when an excess of uric acid is present in the blood; and Cantani's patients would often have some excess of uric acid in the blood as they took some meat, so that milk and cheese might precipitate gout in them, but not in one of my patients; and the case mentioned above was a beginner who had not got free from uric acid. Many meat-eaters suffer from constipation, but not all, and one must, of course, give a different diet to those who suffer and to those who do not. Those who can take breadstuffs freely generally do well to live on them ; but many, myself among the number, cannot take enough bread, and must add milk and cheese to a small extent or starve. In my case this is due to an error in education, for if I had been brought up on breadstuffs I could easily have lived on them now.No one ever swallows uric acid with impunity; but each, as he learns this and comes to change his diet, must decide which foods suit his disease his stomach, his teeth, his age, and his habits, which last have grown to be a part of him.

(Signed)'A. Haig.'

I read this autumn, according to my custom, the epitome in the ' Times,' of the speeches which a number of our greatest doctors addressed to their pupils on the reopening of the schools, and it is a remarkable thing that in those speeches there was not one word of instruction, or, indeed, the smallest allusion to the fact that it was either desirable or possible to keep people from being ill at all.

Just as I reached the end of my notes comes the thrilling account of the Berlin conference on Tuberculosis. It is a disappointment to me to find that there has not been sufficient investigation made during the last eighteen months to confirm or refute Dr. Koch's theory that the bovine tubercle is not transmissible to man. It is, however, cheering to find that Dr. Koch is himself as firm as ever in his belief that overcrowding, damp, want of fresh air and sunlight are the predisposing causes to consumption, and that we must abolish these unhealthy conditions if we would successfully fight the monster which preys on so large a proportion of our population. He also refers to a point I have often been surprised to see so much neglected, viz. that while people will take care not to drink unboiled cow's milk, they cheerfully eat butter and cheese without any sterilising precautions.