Secrets of Earth and Sea

by Sir E. Ray Lankester

THE STORY OF LIME-JUICE AND SCURVY

FROM mediæval times onward a serious constitutional disease—a morbid condition of the blood and tissues—has been known by the name "scurvy," and the word "scorbutic" has been coined from it. It is to-day practically unknown in the ordinary conditions of civilized life, but formerly was common, and the cause of disablement and of frightful mortality in ships' crews, beleaguered cities, armies on campaign, and war-stricken regions. It begins with a certain failure of strength. Breathlessness, exhaustion, and mental depression follow. The face looks haggard, sallow, and dusky. After some weeks the exhaustion becomes extreme; the gums are livid, ulcerated, and bleeding; the teeth loosen and drop out; purple spots appear on the skin; ulcers break out on the limbs; effusions of blood-stained fluid take place in the great cavities of the body; profound exhaustion and coma follow; and death results from disorganization of the lungs, kidneys, or digestive tract. It was recognized in early times that the disease was dependent on the character of the food of those attacked by it; and not the least of the horrors accompanying it was the terror caused by the well-founded conviction that the appearance of a single case in a ship's crew or other specially circumscribed community was an unfailing index, and meant that all were likely within a few days—owing to the enforced identity of their food and conditions of life—to develop the disease. Often, in past centuries, a half or two-thirds of a ship's company have been carried off by it before a port could be reached and healthy food and conditions of life obtained. At the present moment in view of the actual condition of Europe, it is a fact of very grave importance that scurvy is known to break out and cause a terrible mortality among civil communities in time of scarcity—especially in prisons, workhouses, and other public institutions, which are the first to suffer deprivations when food is scarce.

Three hundred years ago it was held that fresh vegetables and fruit-juices were both a cure for and a preventive of scurvy, or "anti-scorbutic." But the fact was not appreciated by Army and Admiralty officials that dried vegetables, even of kinds which were held to be especially "anti-scorbutic," would not serve in place of fresh ones. In 1720, dried "anti-scorbutic" herbs were supplied to the Austrian Army when suffering from scurvy; but they were of no avail, and thousands of the soldiers perished from the disease. A few years later, the British Lords of the Admiralty (actuated by a spirit of blundering parsimony) proposed to supply the Navy with dried spinach, although it was well known that dried vegetables were useless against scurvy. In the American Civil War, 1861-1865, in spite of this knowledge, large rations of dried vegetables were supplied to the armies, and failed to prevent outbreaks of scurvy. Even at the present day so little attention has been given of late years to the subject, that many ignorant officials, upon whose action the life of thousands depends, regard dried vegetables as equivalent in value to fresh!

A great advance was made in the second half of the eighteenth century, when the British Admiralty became convinced by the repeated experience of its officers that "lime-juice" is a specific remedy and preventive for scurvy, and, in spite of the great expense and difficulties entailed, adopted its use officially. In those days of sailing-ships, long voyages (such as those of Captain Cook) were safely carried through without serious outbreak of scurvy so long as a ration of so-called "lime-juice" (about one ounce) was swallowed each day by each sailor. But it was not until the beginning of the nineteenth century that the disease was practically eliminated from the Navy by the introduction (after many foolish delays) of a general issue of what was called "lime-juice."

The complete control and elimination of scurvy by the use of so-called "lime-juice" sufficed to carry us on until the introduction of steam navigation, when it became superfluous owing to the fact that long absence from land, where fresh food could be obtained, ceased to be usual. Moreover, after a mutiny on the part of our defrauded sailors, better food and greater variety of it was secured for them, and the profits of murderous contractors were stopped.

The history of outbreaks of scurvy for the last century is practically confined to the experiences of Arctic Expeditions and the campaigning of troops in remote or devastated regions. So little had scurvy been investigated, or any serious study made of the nature of the remedial and preventive action of lime-juice, that up to the year 1914 it was regarded as a matter of course that the acid, the citric acid, of lime-juice was what gave to it its virtue, and samples of lime-juice supplied by contractors were tested solely as to the percentage of that acid present. Eminent medical authorities proposed to use crystals of citric acid in place of the juice; others declared that vinegar would do just as well; others, in spite of the overwhelming record as to the value of lime-juice, held that scurvy was due not to the absence of a food constituent—supplied by fresh vegetables and fruit-juice—but to a peculiar poison present in the salted and dried meat served out as rations; others again, without any study of the disease, have expressed the opinion that it is due to a bacterial micro-organism.

A blow to the easy-going belief of the Admiralty that they had mastered and made an end of scurvy was struck when scurvy broke out (60 cases among 122 men) in the expedition to the North Pole which sailed in May 1875 in the Alert and the Discovery, under the command of Sir George Nares. The expedition had to return prematurely after seventeen months' absence, and a committee was appointed to inquire into the cause of the outbreak. The stores of food and of lime-juice were shown to have been ample; and the action of the leader in equipping his sledging parties was in accordance with the judgment and experience of successful explorers who gave evidence. The cause of the outbreak remained a mystery. The firm belief in the anti-scorbutic powers of "lime-juice" was shaken, and this unfavourable opinion of its value has been confirmed by medical officers who, during the recent war, have been confronted by outbreaks of scurvy. These outbreaks occurred among troops who, in military circumstances which rendered an adequate supply of fresh meat and vegetables impossible, were supplied with lime-juice prepared from the West Indian "sour-lime."

Under these circumstances, an experimental study of scurvy has been carried out during the last four years by a group of workers at the Lister Institute, together with a historical inquiry as to the use of lime-juice. The reports of these investigators have very great practical value and far-reaching interest, as showing what disastrous results may arise from inaccurate use of a word, and the neglect to ascertain the exact nature of the material thing upon which the issue between life and death may depend.

Here let me say that the staff of the Lister Institute for medical research has done work in its laboratories in Chelsea Gardens of the very greatest national importance during the war. It was founded by public subscription, and has now an endowment of some £10,000 a year. Sir David Bruce, the chairman of its Council, gives in the Report of the Governing Body for 1919 a very striking summary of the work done in the laboratories and by the staff of the Institute. The successful investigation of trench fever and of tetanus, of the destruction of lice, and of the effects of cold storage on food, besides the study of scurvy and other diseases due to deficiency of what are now called "accessory food factors," are, we learn, the chief matters in which the Lister Institute was engaged in the year 1918-19. Besides this, however, at its farm at Elstree it has prepared and supplied to the War Office, the Admiralty, the Overseas Forces, and the Local Government Board more than a million doses of anti-toxins (diphtheria and tetanus), bacterial vaccines (cholera, plague, influenza), and other similar curative fluids—requiring for their safe production the highest skill and most complete knowledge of recent discovery. And this is only a sample of what the Lister Institute has been doing for many consecutive years.

Now we return to the investigation of scurvy. Within the last ten years the fact has been established (which was more or less guessed and acted upon by medical men of past days) that, in order to maintain health, the diet of man and of many animals must contain not merely the necessary quantities of meat or cheese-like bodies, of fat and starch and sugar, but also minute quantities of accessory food-factors which it is convenient to term "vitamines." The name serves (though its etymology is unsatisfactory) to indicate certain "proteids" or highly complex nitrogenous compounds which are only to be obtained from fresh and uncooked or slightly heated vegetables and from some foods of animal origin. These "vitamines" are destroyed by heat and by desiccation. They have not yet been isolated though in some cases extracted in a nearly pure state. Their presence or absence is demonstrated by careful experiments in feeding animals, such as guinea-pigs, with weighed quantities of different foods. The "vitamine" is often found to be present only in one part of a seed or fruit or special kind of fat liable to be rejected in food preparation. An important fact is that it may not amount to as much as one-ten-thousandth of the weight of the food in which it occurs; and the part containing it may be overlooked and rejected, or its value destroyed by heat or by desiccation. A committee on these "accessory food-factors" is carrying on experiments at the Lister Institute. Dr. F. G. Hopkins, F.R.S., who first discovered the importance of one of these factors in feeding young rats, is the chairman, and Dr. Harriette Chick is the secretary. Three kinds of these vitamines, or accessory food-factors, have up to this date been recognized. The first is the anti-neuritic or anti-beri-beri vitamine. Its principal sources are the seeds of plants and the eggs of animals—yeast-cells are a rich source of it. Where "polished rice," as in the Far East, is the staple article of diet, to the almost entire exclusion of other food-stuffs, lassitude and severe pains like those of rheumatism set in, and a whole colony or shipload of Chinese "coolies" may be disabled. The disease is called beri-beri, and it can be cured by administering that part of the rice-grain (the skin and germ) which is removed by "polishing," and unfortunately is just that part which contains the needful vitamine. It exists in very minute quantity, amounting to only one part in ten thousand by weight of rice-grain. The second "vitamine" recognized is the anti-rachitic factor (studied by Hopkins), which tends to promote growth and prevent "rickets" in young animals. Certain fats of animal origin (milk) and green leaves contain it in minute quantity, and are necessary for the life of young animals and for the health of adults.