Regretfully we tore ourselves away from the magic attractions of the mountains and sped to Havana. We had had a glorious trip, a trip of real discovery, one might say, and were duly thankful for the memories we carried with us. Pleasant they were, though rather disconcerting after there was time. for thought. We had seen the hoyo, the one place in the world where they raise perfect tobacco. But had we pried into Cuba's secret, after all? Again and again came the question, why does the hoyo raise perfect tobacco? There is no question about the fact; the manufacturers admit it; the growers take pride in it. The price proves it. If more conclusive proof is wanted, it comes from the hoyos themselves. Would such a place as the Hoyo Palenque, surrounded by cliffs over a thousand feet high and reached by seventy separate ladders, have been cultivated for over a hundred years if it did not produce a superfine product? There is but one answer to this, but the reason is not so easy. I believe I have unriddled the riddle, but mark that I only say "believe."

The limestone cliffs give their aid of course, since tobacco must have a slightly alkaline soil. But then lime is not a scarce article in this world of ours and its effects can be duplicated elsewhere. Again, there is the sterility of the peculiar type of sandy soil which makes up Cuba's good tobacco land. It may have unique chemical properties that contribute to the end result. Since they have never been studied carefully, one can not say, but this does not seem a necessary assumption. The fact that there is that agricultural ideal, a perfect climate, backed up by a sterile soil of proper physical constituency, is all that is necessary to account for the generally excellent tobacco of certain areas of the celebrated Vuelta Abajo. Doesn't it seem like an agricultural paradox to attribute the excellence of a product to the sterility of the soil? It is the truth, however. Several years ago it was found that a tobacco plant produces about the same quantity of the essential oils that give the leaves their aroma no matter whether certain of the conditions under which it is grown be good or bad. In other words, if a plant grows to be eight feet high and has leaves twenty-six inches long, it produces only about the same amount of essential oils as when it grows two feet high and has leaves eight inches long, other things being equal. Now it is a noteworthy fact that while Cuban tobacco under shade in Connecticut meets the first of these conditions, the average Cuban plant hardly approaches the second. The Cuban plant is a dwarf, and packs into its small self as much of the essentials of real

VOL. VII.-12.

quality as its giant sister in Connecticut. Here again, however, our interpretation fits Cuban tobacco in general. The conditions are met just as neatly in the ensenada as they are in the hoyo, so we still seem far off the mark. This is not the whole story, for we must remember that the hoyo has and uses all 'these advantages as a basis upon which to build its own perfecting qualities.

The hoyo itself is the secret of the matter. Why do they grow tobacco under shade in Connecticut, Florida and even Cuba? Simply because it conserves moisture and keeps the temperature and humidity constant and high. This the hoyo does naturally with its limestone cliffs, having withal the immense advantage of direct rays of the sun at a considerable altitude, factors known to be essential to other crops besides tobacco. And it has the sun when it needs it, enough and no more. From ten o'clock until three it shines directly on the plants, storing up food in the leaves for elaboration during the night, while from dawn until ten and from three until seven, there is indirect light due to the protecting cliffs. It is a stage setting that could not be more admirable from the standpoint of plant physiology, a perfect fulfillment of what are known to be the conditions required by the tobacco plant.

The reason why other countries can not compete with Cuba in producing the fragrant weed, therefore, is not so difficult to see. They may improve their methods of cultivation and manufacture, select carefully their soils and climate, may even imitate conditions artificially with tents and tent-poles; but they can not hope to duplicate the finest product until they find a wizard genius who can transport the ancient hoyos far beyond the sea, and train the sun to obey his word as did Joshua of old.

VITAMINES AND NUTRITION

By Dr. H. STEENBOCK

ASSOCIATE PROFESSOR OF AGRICULTURAL CHEMISTRY, UNIVERSITY OF WISCONSIN

S

INCE 1912 when Casimir Funk first brought to the attention of the public the hitherto unknown dietary essentials under the collective term vitamines, nutrition experts have felt that they had something tangible to investigate-something the importance of which it was necessary to prove or disprove. As experimentation revealed symptoms attributable to vitamine deficiency, the general public, ever easily impressed by matters unexpected, and matters so vital as to revolutionize the conception as to what constitutes an adequate diet, soon became alarmed. At present it is probably not overstating the situation when it is said that the previously considered all-important attributes of an adequate ration, such as sufficient protein, calories and salts, have probably been slighted by the sudden interest taken in vitamines. Nor is this so very remarkable. Certainly no individuals have been more impressed with the important rôle that vitamines have in the diet than the investigators engaged in this field of nutrition. Only a few years ago students were taught that the body needed energy, to be furnished by carbohydrates and fats, protein, to be furnished by proteins, and inorganic elements, to be furnished by ash These, together with water, were supposed to constitute the sum total of the dietary requirements of the animal body. Imagine the surprise and chagrin of the nutrition experts when it was found impossible to support the life of an experimental animal, such as the rat, on a ration compounded from these elementary highly purified food stuffs. Lack of palatability resulting in insufficient consumption was given as the reason. "How," was it asked, "can an animal maintain itself when the lack of taste to the food leads to loss of appetite?" "Our naturally occurring foods contain esters and ethers which induce better consumption and therefore maintenance." But, on investigation, it was found that a great substantial variation. in the taste of the ration by the addition of flavoring extracts of great variety in kind and amount did not improve the nutrition of the animal. Not until there were added small amounts of certain plant or animal tissues or their extracts-now known

1. A pigeon showing a neck spasm in an acute attack of avian beri-beri (polyneuritis) resulting from the consumption of a ration deficient in water-soluble vitamine.

to furnish the vitamines-was it found possible to induce normal nutrition. Certainly the public is to be excused, if, as the result of the enthusiasm of the investigator, it shows undue concern over the vitamine content of the daily diet.

Let us analyze the situation more minutely from the experimental standpoint, so that we can comprehend what is definitely known in regard to vitamines, what physiological disturbances are to be expected if our diet is deficient in them and what with our present mode of living is the probability of a deficiency.

Generally it would be inferred from the term, as Funk implied, that vitamines are substances of an amine nature concerned with vital phenomena. Though certain derivatives of ammonia have been shown to have some of the properties of vitamines, yet of their amine nature there is conclusive proof. Of their relation to vital phenomena there is absolutely no question. Physiologically, vitamines can be divided into at least two types. Both are soluble in water, but only one is soluble in fats. This difference in properties has led to their characterization, respectively, as a water-soluble vitamine and as a fat-soluble vitamine. Though possible, yet in the light of present information it can not be considered probable that either type consists of more than one active component. Chemically, in even an approximately pure form, both vitamines are entirely unknown. Without either kind in the diet, animal life, at least that high in the genetic scale, is impossible.

Curiously enough, the observations of symptoms indicative

of a lack of the water-soluble vitamine in the dietary were made on man himself. In the far east, especially in the Malay peninsula, in the Philippines and in Japan, there has been prevalent a disease known as beri-beri. It is characterized by a loss in weight with muscular atrophy, contracture or paralysis. It may run a rapid course, ending in sudden death, due to heart failure, or it may take on a chronic form. On post mortem there is evidence of more or less edema and extensive degeneration of nerve elements. Though these cases were of quite frequent occurrence, economically this disease was first brought to the attention of the civilized world when, during the Russian-Japanese war, a considerable portion of the Japanese army was incapacitated by its ravages.

Fortunately,

2. A young female albino rat suffering from polyneuritis due to a deficiency in its diet of the water-soluble vitamine. Note the abnormal curvature of the back and especially in the one photograph an extreme spasticity. This rat should normally have weighed 120 grams; its actual weight was 54 grams. A rat in this condition without treatment will usually die in 10 to 24 hours.