Letter to Karl Marx, August 21, 1857

ENGELS TO MARX

IN LONDON

Waterloo, 21 August 1857

Dear Moor,

You will have received the articles this morning.^[1]

I do, indeed, regard your theses as OPEN TO SOME OBSERVATIONS. That iron takes effect in 3 weeks as compared with 3 months for cod-liver oil is surely not to be taken literally. There could be absolutely no question of a disease of this kind being cured in 3 weeks; on the contrary, I should say that, iron or no iron, cases have more often been known to take 3 years rather than 3 weeks to cure.

That lack of iron in the blood is a primary characteristic of scrofula is certainly news to me. But whatever the literature on the subject, there is no doubt that, for some time past, it has become increasingly the fashion to reduce all diseases to lack of iron in the blood, a fashion which is already beginning to evoke a reaction; as to the disease of which, more than any other, this is known to be the primary characteristic—anaemia—some Frenchmen have latterly declared that iron has nothing at all to do with it. Exactly what the primary characteristic of scrofula is would seem to be still far from clear.

That iodine is one amongst others of the principal elements responsible for the effect of cod-liver oil is not in doubt. But it is

by no means the only one. If one takes iodine in other forms one doesn't make such good progress. Besides, cod-liver oil contains chlorine and bromine, both of which have a direct or indirect effect on the disorder, and to what extent that effect is helped by the gall constituents and volatile fatty acids has not yet been established. All I know is that Norwegian cod-liver oil, which has the bitter taste of gall, has done me more good than the Newfoundland or English product, which does not taste of it.

I took iron iodide all the time I was in Manchester (in between London^[2] and Waterloo^[3] ) along with cod-liver oil, and the inflammation grew steadily worse until finally it became chronic. Since I have been here I haven't taken any more iron iodide and Heckscher and I agreed long ago that either iron iodide or Quévenne's iron should be used in after-treatment.

The fat in cod-liver oil is, pour le moment,^[4] by no means useless ballast so far as I am concerned. Since regaining my strength, I am again accumulating fat. Needless to say, my diet may contain only a small proportion of ready-formed animal fats. Consequently I have to eat more starch flour and, in fact, I sometimes feel a positive craving for bread; I am eating twice as much meat, but four times as much bread as I usually do. The fat in cod-liver oil is an invaluable aid to this battening process, being taken in an exceedingly innocuous form and less of an irritant than animal fat or things cooked in fat.

So you see, iron has never been completely out of our view and, even after I had been taking it for more than 3 weeks without any result (and it may, indeed, in the then circumstances, have made matters worse), we have nevertheless already reserved it for my after-treatment. Heckscher, to whom I spoke about iron last Sunday, was definitely against my taking it again at this juncture, in view of previous experience, and I must agree with him. Later, of course. I repeat that, despite the unanimity of the literature on the subject, I shall continue to entertain grave doubts about the reduction of all diseases to iron shortage until we know more than we now do about the condition and the normal level of iron in the blood. At all events, / had sufficient iron in my blood at the start of this business, as any of the doctors who saw me at the time can testify. I am perfectly willing to believe that people of definitely scrofular habit—pallor, transparent skin, etc.—may be suffering from a shortage of iron.

But admis^[5] that this is the basic character, the INDISCRIMINATE and immediate use of iron is by no means indicated. It is extremely difficult to introduce iron into the blood otherwise than in the small amounts contained in ordinary food. Assuming, then, that the nature of my disease was the inability of the blood to assimilate the iron in food, how much less would it assimilate the iron in medicine? Sea air and sea bathing so invigorate the system as to restore the blood's ability in this respect. Thus it again assimilates the iron in meat and bread and, since I am eating more than formerly, concomitantly more iron. It is now, when this ability has been restored, that iron taken medicinally can help, although I believe that 9/i0 of it passes through the body unused and, even if one accepts the iron theory, the use of iron during every phase of the disease has been shown to be incorrect. On top of which one has to consider the wide variety of individual cases and constitu- tions. I myself, for instance, appear to be particularly sensitive to all metals; even the external application of quicksilver to prevent the local spread of the inflammation took effect very rapidlyfin my case, and it is quite possible that iron iodide, taken at a time when my blood was too disorganised to assimilate it, helped aggravate the inflammation.

At all events, and even admitting the iron theory, I don't see how your theses materially confute the assumptions in my previous letter,^[6] in which I was, by the way, considering only the immediate use of iron, not in any specific form, and ruling out cod-liver oil.

Today I bathed in the sea for the first time. It did me no end of good and made me ravenously hungry. For the time being I am to bathe only every other day.

But now it's time for the post. Am working on 'Army'. Many regards to your wife and children.

Your

F. E.