The sulphuric compounds are related and yet opposed to the growth determinating phosphoric compounds. All organic building material (protein) contains phosphorus and sulphur, in varying proportions, and all indications are that sulphur plays the part of a regulator in organic growth. Just as an engine requires a governor to regulate its pace, so the human body requires a controlling factor to ensure definite stability. It is interesting to observe that normal blood contains about twice as many sulphates as phosphates. When there is great scarcity of sodium sulphate in the blood, abnormal growths develop from the phosphatic nerve tissues, and they continue to develop so long as the blood and lymph are deficient in sulphur, particularly the sulphates. This is, I believe, the genesis of polyps, tumors and cancers.
In the same manner that sulphuric acid controls and regulates the phosphoric acid of ammonium phosphate, so lime and magnesia act on the ammonia of this same ammonium phosphate.
Phosphatic ammonium carbonate lodges in the gelatinous cartilage and stretches it, when there is a deficiency of lime and magnesia in the food, resulting in rickets. Such a growth of cartilaginous tissues is controlled by lime and magnesia, as they change the pliant cartilage into bony barriers in which small particles of magnesia combine to produce phosphate of ammonium and magnesium which checks the further deposit of cartilage.
Lime and magnesia are indubitably quite as effective agents in the control of ammonia as sulphur is in the control of phosphorus. If we consider the minerals as the foundation and mortar which give stability to the vital machine, leaving out chlorine and fluorine, we find that iron, manganese, potash, soda, and silicic acid play this role. Sulphur, because it possesses the property of becoming gaseous, is able to take part directly in the formation of albumen, that variable basis of body material, whereas all of the other mineral substances except silicic acid can only be assimiliated in so-called binary compounds in the form of salts.
I will give a brief review of them, beginning with iron, as thus the significance of augmentation of the mineral content of vegetables and small fruits and eggs will be made much clearer.
Normal blood albumen is essentially a compound of calcium and sodium into which iron and sulphur both enter. A deficiency of calcium commonly makes itself known by dental defects, just as lack of sulphur reveals itself by the falling out and poor growth of hair. Insufficiency of iron in the blood is evidenced, apart from lack of spirit, by paleness of face and blue lips; insufficient sodium by glandular tumors and abnormal cartilaginous growths.
The entire amount of iron in the blood of an adult person is, on the average under normal conditions, four grams, as much as a nickel weighs. We may well judge that this amount is not sufficient to set the motive power of our bodies in action, if we overlook that complex factor the circulation of blood. The left side of the heart has the capacity of containing about six ounces of blood, and every heart beat drives this amount through the aorta. With seventy beats to the minute, twenty-five pounds of blood is pumped from the heart every minute. What is the result? That the four grams of iron keep up such an incessant movement that they pass from the heart into the aorta sixty times an hour or 1440 times in 24 hours. It may be asserted, therefore, that in 24 hours 13 pounds of iron (that is 1440x4 grams) pass from the heart into the aorta. Can it be doubted, in view of this, that the iron serves to produce an electro-dynamic force?
In respect to the generation of electricity, it matters not whether there be an entirely new supply of iron passing a given point, or whether the same iron pass that point anew each minute. Two factors work together in the circulation of the blood, namely, the active attraction of nerve tissue and the passive susceptibility of the blood contents to that attraction. Faraday has conclusively shown that blood is magnetic in character because of the iron it contains. If four grams of iron is the normal quantity in the blood, it is clear that the reduction of this amount, say by two grams, will lessen its susceptibility and slacken its circulation. The electrical nerve ends will then strain in vain for the electricity which the blood current should yield, and the result will be neuralgia.
It is the magnetic iron in haemoglobin which makes every sort of nervous function possible, in the cerebral (brain) and in the sympathetic (intestinal) tracts, and since it is thus made clear that intellectual activity on the one hand and breathing and digestion and excretion on the other are dependent on the iron content of the blood, we must also recognize that, as iron attends every nerve action, the secretion of urine too takes place under the influence of haemoglobin. Insofar as haemoglobin hastens the departure of the excrementitious matter in urine out of the system, there is a daily loss of iron in the urine. This loss in the form of urohaematin may total four centigrams, or a hundredth part of our supply.
This loss of iron if not replaced by eating suitable food will soon make itself felt. In the course of a day the reduction by four centigrams will diminish the energy of nervous activity about 1440 times the apparent loss, so that even a four weeks-tropical fever, during which no meat is eaten, may completely exhaust the strength of an individual. Moreover, iron conditions bodily warmth as it combines with oxygen in a higher and a lower degree. In the lungs it is highly oxidized by the respired oxygen, but in contact with the nerve ends it gives itself only to a part of the oxygen present, and burns a certain portion of the lecithin to water, carbonic acid and phosphates, thus creating body warmth to a considerable extent.