I shall not tarry long to speak of the nature of this ferment, for the studies bearing upon that point, although far advanced, are not yet completed. I may remark, however, that the idea that the ferment is formed of living organisms is a very old one, and has not arisen suddenly because of the modern theories of the parasitic nature of disease. From the time of Varrar (who believed that malaria was made up of invisible mites suspended in the atmosphere) to our own day this theory has been several times advanced by hygienists. Independently of the general considerations which led Rasori, and later Henle, to formulate the doctrine of the contagium vivum of infection (long before the progress of microscopical science had revealed the existence of living ferments), there were peculiar circumstances as regards malaria which should have impelled minds to look in that direction, even in times long past.

Some of these circumstances are of a nature to strike every serious observer, and deserve a few moments' attention. How could one maintain, for example, that this ferment is a product of chemical reactions taking place in the ground, when it is seen to remain constantly the same whatever may be the composition of the soil from which it emanates! As long as the paludal theory held sway, the chemical interpretation of this identity of the product in every latitude was easy. Rica does not hesitate to admit that when a swampy tract is heated by the sun's rays to the necessary point for the putrid decomposition of the organic matters contained in it, the "chemical ferment," or rather the "mephitic gases," to which is attributed the morbific action, are developed, whatever may be the distance from the equator at which this marshy region lies. But since it has been ascertained that malaria is produced in soils of the most varied chemical composition, the persistent identity of this product has become chemically inexplicable; while it is however readily conceivable, if one admits that malaria is an organized ferment which easily finds the necessary conditions for its life and multiplication in the most varied soils, as is the case with millions of other organisms vastly superior to the rudimentary vegetables which constitute the living ferments.

The same thing may be said of the progressive intensity of the morbific production in abandoned malarious districts. This fact has been historically proved in several parts of the earth, and especially in Italy. A large number of Grecian, Etruscan, and Latin cities, even Rome itself, sprang up in malarious territories and attained a high state of prosperity. First among the reasons for this success must be placed the works undertaken with a view of rendering these places more salubrious, and which lessened the evil production, but almost never extinguished it completely. After the abandonment of these localities, the production of malaria recommenced in a degree which went on increasing from age to age, and which has rendered some of these places actually uninhabitable. This was seen, in the time of the ancient Romans, in Etruria, when it was conquered and laid waste, and in several parts of Magna Graecia, and of Sicily. From the fall of Rome even to the present day, this phenomenon has been manifested in a very evident manner in the Roman Campagna, in certain parts of which, even up to the time of the Renaissance, it was possible to maintain pleasure houses, but which are now unhabitable during the hot season. In many cases the physical conditions of the soil have undergone no appreciable change during centuries, so that it is impossible to attribute so enormous an augmentation of malaria to an increase in its annual production, itself increased by a progressive alteration of the chemical composition of the soil. But if, on the contrary, it be admitted that malaria is caused by a living organism whose successive generations accumulate in the soil, the interpretation of this fact becomes very simple.

There are, finally, peculiarities in the local charging of the atmosphere with malaria which can be explained only in this manner. If the malarial miasm were composed of gaseous bodies emanating from the soil, or rather of chemical ferments formed beneath the ground and raised into the air by gases or watery vapor, the charging of the atmosphere with the specific poison ought to arrive at its maximum during the hottest part of the day, when the ground is heated the most by the sun's rays, and when the evaporation of water and all chemical actions attain their maximum intensity. But this is very different from what actually occurs. The local charging of the atmosphere is always less strong during the meridian hours than at the beginning and the end of the day, that is to say, after the rising, and especially after the setting, of the sun. Now it is precisely at these hours that the difference between the temperature of the lower layers of the atmosphere and that of the surface of the ground is the greatest, and that the ascending currents of air starting from the ground are the strongest. If malaria consists of solid particles contained in the soil, one may readily understand how their elevation en masse into the atmosphere should take place especially at these two periods of the day.

All these facts, which can be easily verified if the subject of malaria be studied on the spot and without any preconceived notions, explain the tendency which has always been manifested to attribute this specific poisoning of the air to a living organism which is multiplied in the soil; and they also explain the ardor with which hygienists have applied themselves to the production of the scientific proof.

Unfortunately the investigations undertaken for this end have for a long time been fruitless, for the preconceived paludal theory has led investigators to occupy themselves exclusively with the inferior organisms inhabiting marshes. Among these organisms they studied especially the hyphomycetes, which had already acquired so great an importance in dermatology; and their entire attention was concentrated upon the aquatic algae, without even taking the precaution to determine whether the varieties which they thought to be malarial were found in all malarious swamps, or whether they were capable of living within the human organism. It has thus happened that each observer has indicated as the cause of malaria a different variety of alga, whichever he found to be most abundant in the swampy ground that he had to examine. Thus Salisbury has indicated the palmella gemiasma, which is found with us in places perfectly free from malaria, while it is often wanting in malarious marshes in the center of Italy; Balestra, a species of alga which is as yet indeterminate; Bargellini, the palmogloea micrococca; Safford and Bartlett, the hydrogastrum granulatum; and Archer, the chitonoblastus oeruginosus. There is not a single one of these species the parasitic nature of which has been demonstrated; and as regards the two last named varieties, it can be positively denied that they are capable of producing a general infection, for the diameter of their spores and filaments is greater than that of the capillary blood vessels.

It was only in 1879 that Klebs and myself, after having been thoroughly freed, by a long series of preparatory studies, from the unfortunate paludal idea, undertook together some investigations in malarious districts of the most varied character, marshy and not marshy. We employed the system of fractional cultivation, making experiments on animals with the final products thus obtained. We felt ourselves justified in recognizing the malarial ferment in the schizomycete bacillus. The numerous researches made subsequently by us, and by many other observers, in the soil and in the air of several malarious localities, as well as in the blood and in the organs of men and animals specifically infected, have put it henceforth almost beyond doubt that we really have to do with a schizomycete. Very recently, MM. Marchiafava and Celli have succeeded in demonstrating that the germs of this schizomycete attack directly the red blood-globules, and destroy them, causing them to undergo a series of very characteristic changes which admit of easy verification, and which render certain the existence of a malarial infection.

Several observations made recently in Rome tend to demonstrate that the schizomycete of malaria does not always assume the complete bacillary form described by Klebs and myself; but this morphological question possesses no further interest for the hygienist. For him the essential thing is to know that he has to deal with a living ferment which can flourish in soils of very varied composition, and without the presence of which neither marshes nor stagnant pools of water are capable of producing malaria.

We must not think, however, that all earth containing this ferment is capable of poisoning the superjacent atmosphere. Popular experience, certain modern scientific investigation, and the facts which one can often verify when the soil, which was malarious in ancient times and which has since ceased to be so, is turned up to a great depth, all agree in proving that the ground remains inoffensive as long as it is not placed in certain conditions indispensable for the multiplication of this specific ferment. Up to this point the organism lives, so to speak, in an inert state, and may remain so during centuries without losing any of its deleterious power. There is nothing in this fact that ought to surprise us, since we know that the life and the power of evolution belonging to the seeds of plants of a much higher order than these vegetable organisms constituting ferments, may remain latent for centuries, and may then revive at once when these grains are placed in the conditions suitable for their germination.

Among the conditions favorable to the multiplication of the malarial ferment contained in the soil, and to its dispersion through the superjacent atmosphere, there are three which are absolutely essential, and the concurrence of which is indispensable for the production of bad air (malaria). First, a temperature which does not fall below 20 deg.C. (67.5 deg.F.); next, a very moderate degree of permanent humidity of the soil; and finally, the direct action of the oxygen of the air upon the strata of earth which contain the ferment. If a single one of these three conditions be wanting, the development of malaria becomes impossible. This is a point of prime importance in the natural history of malaria, and it gives us the key to most of the methods of sanitary improvement attempted by man.

Let us see first what can be done in this direction without the labor of man. For nature herself makes localities salubrious by suspending for a greater or less time the production of malaria. It is thus that winter brings about in every country a freedom from malaria which is purely thermic, for it is due simply and entirely to a sinking of the temperature below the required minimum. Indeed, if the temperature in winter rises above this minimum, there are often sudden outbreaks of malaria. Sometimes, during very warm and dry summers, the heat extracts all the humidity from the malarious soil, and thus procures for us a freedom from the disease which is purely hydraulic. This may continue for a long time (as happened in the Roman Campagna during the years 1881 and 1882), but may also be completely destroyed by a single shower. Nature also sometimes renders a district healthy in a manner purely atmospheric, by covering a malarious soil with earth which does not contain the malarial ferment, or with a matting formed of earth and the roots of grasses growing closely together in a natural meadow.

In the attempts of purification by suspending the malarial action, which have been devised by man, the same thing has been done; that is to say, it has been sought, to eliminate at least one of the three conditions essential to the development of the specific ferment contained in the infected soil. Naturally, they have not thought of bringing about a thermic purification, such as nature produces in winter, because of the impossibility of moderating the action of the sun; but they have tried from all time to procure hydraulic or atmospheric purifications, and sometimes to combine these together in a very happy way.

The hydraulic systems are very numerous, for the problem which is presented, namely, that of depriving the ground of its humidity during the hot season, necessitates different solutions according to the nature and the bearing of the soil. Sometimes this is done by digging open or closing ditches intended to draw away large bodies of water. At other limes a system of drainage is established, by means of which the water is drawn out of the earth and its level is depressed, so that the upper malarious strata, exposed to the direct action of the air, are deprived of moisture during the hot season. This system of drainage is not a modern invention; the Italian monks understood it as well as, and even better than, we do. In deep and loose soils they used sometimes, just as we do now, porous clay pipes; but when the subsoil was formed of compact and nearly impermeable matters, they employed a system of drainage, the extent and grandeur of which astonishes us. It is that of drainage by cavities, applied by the Etruscans, Latins, and Volsci to all the Roman hills formed of volcanic tufa, the tradition of which I have found still preserved in some countries of the Abruzzi.

We may sometimes establish a double drainage, from below and from above; that is to say, to drain the subsoil, and at the same time increase the evaporation of water from the surface of the ground. It is well known that clearing off the forests of malarious countries has often proved an excellent means of making lands salubrious which were before too damp; for, by removing every obstacle to the direct action of the sun's rays upon the ground, we cause an increase of evaporation from its surface, and may thus be enabled to exhaust the superficial strata completely of their water during the hot season. In very moist lands, which lend themselves readily to deep drainage, the combination of the latter with a clearing of the surface has, in almost every quarter of the globe, rendered possible a very widespread and sometimes a quite lasting freedom from malaria. But, although a nearly universal experience proclaims this fact, there is a school which, following in the footsteps of Lancisi, maintains the contrary opinion, that it is necessary to preserve the forests in malarious districts, and even to increase their extent, since the trees filter the infected atmosphere and arrest the malaria in their foliage. This strange theory was formulated by Lancisi in 1714, on the occasion of the proposed clearing of a forest belonging to the Caetani family, and lying between the Pontine Marshes and the district of Cistema. Lancisi was completely imbued with the paludal notion, and consequently believed that the very severe malaria of Cistema was brought by the winds from the coast marshes, instead of being produced in the soil surrounding the district, which was then covered by this forest. He believed then that the forest acted as a protective rampart, and he prevented its being cut down. But toward the middle of the present century the Caetani had the woods cleared off from the entire belt of land surrounding Cistema. Twenty years later I was able to show that Cistema had gained greatly in salubrity. I published my observation in 1879, and, naturally, was taken to task rather sharply in the name of the sacred tradition. Happily these recriminations led our Minister of Agriculture to have the question studied by a special commission. This commission, after a conscientious examination extending over three years of all the malarious localities in the province of Rome, has just published its report,[1] the conclusions of which are entirely in accord with the facts of universal experience. They were not able to verify a single fact in support of Lancisi's theory, while they found many of the same nature as that of Cistema, and which have resulted in overturning the theory entirely.

[Footnote 1: Della influenza dei boshi sulla malaria dominante nella regiona marittima della provincia di Roma. Annali di Agricoltura, No. 77, 1884. Roma: Eredi Botta.]

It has also been thought possible to practice drainage from above by means of plantations of certain trees which would draw considerable moisture from the earth, a method which might really be serviceable in some malarious districts. But in accordance with the idea that malaria is a product of paludal decomposition, the trees selected have almost always been the eucalyptus. It has been maintained that trees of so rapid a growth ought to drain the soil very actively, and also that the aroma of their foliage ought to destroy the miasmatic emanations. I have hitherto been unable to verify a single instance of the destruction of malaria by eucalyptus plantations, but I do not consider myself justified in denying the facts which have been stated by others. There is nothing to oppose the admission that these plantations, when properly made, may sometimes have been of great utility. I maintain frankly, however, that they have not always been so, and that it is necessary to guard against the exaggerations into which some have allowed themselves to fall in recent times. Such exaggerations might have been avoided if, instead of talking about these plantations on the basis of a theoretical assumption, the results only had been studied in places where the eucalyptus abounds. It would then have been known that even in the southern hemisphere, the original home of the eucalyptus, there are eucalyptus forests which are very malarious. This fact has been demonstrated by Mr. Liversige, professor in the University of Sydney, Australia. Among us also, although everybody was convinced by the statements of the press that the locality of the Tre Fontaine, near Rome, had been freed from malaria by means of the eucalyptus, people were disagreeably surprised by an outbreak of very grave fever occurring throughout the whole of this colony in 1882, a year in which all the rest of the Roman Campagna enjoyed an exceptional salubrity. If, alongside of these hygienic uncertainties, we place the agricultural uncertainties, we must conclude that it is necessary to contend strongly against this fanatical prejudice in favor of the eucalyptus tree. These plants are, in fact, very capricious in their growth. In full vegetation during the winter in our climate, they are often killed instantly by a sharp winter frost, by damp cold, by the frosts of spring, or by other causes which the botanists have not yet been able to determine. At other times, if the winters are very mild, these plants grow too rapidly in height, and then are broken short off by moderately strong winds. It should further be mentioned that these plantations are sometimes very expensive. In fact, if the earth contains too much water, it must be drained under penalty of seeing the roots of the eucalyptus rot. Then again, if the subsoil is compact, it is necessary to dig deep trenches in order to give room to the long roots of these trees, and often indeed these trenches must also be drained, as is done for olive trees. The conclusion evidently is that it is better to confine ourselves to hydraulic methods of promoting the health fulness of a locality, the immediate effects of which are less uncertain. And then, when the local conditions are such as to make it desirable to try the effects of plants possessed of strongly absorbing powers, it is better to choose them from among the flora of our own hemisphere. This is more sure, and will cost less.

Simple hydraulic methods of purification, even the most perfect, do not, however, produce permanent hygienic effects, since the moisture necessary for the multiplication of the malaria in the soil is so slight that these effects may be compromised by anything whatever that is capable of restoring a moderate degree of humidity to the ground during the hot season. It has often been thought that a suspension of malarial production would be better assured by suppressing at the same time the humidity of the soil and the direct action of the oxygen of the air upon the superficial strata of earth which contain the ferment. This has been successfully accomplished by the system of overlaying (comblees). This consists in covering the infected soil by thick layers of uninfected earth, carried there either by the muddy waters of rivers or by the hand of man. At the same time the steady drainage of the surface and underground water is provided for. Last year I advised our Minister of War to undertake in another form a hydraulico-atmospheric purification of the district of the Janiculum surrounding the Salviati Palace on the Via della Longara, by draining the soil carefully and covering with a layer of very close turf all the parts of the surface which could not be macadamized. It would seem as if this system had been rather successful, since there has not been this year a single case of fever in the personnel of the new military college, established in the Salviati Palace; while in the Corsimi Palace, which is situated on the same side of the Via della Longara, but which looks out upon that part of the Janiculum which is still uncovered, there have been some fatal cases of fever.

Furthermore, we have had in Rome, during the past few years, some very evident proofs of the efficacy of atmospheric methods of purification. I will confine myself to the relation here only of the most striking instance, one which has been furnished us in the building up of new quarters of the city. There was much discussion at first as to whether the improvements should be undertaken in the parts where they now are or in the valley of the Tiber, for the uncovered lands of the Esquiline and of the Quirinal were malarious, and, as nearly everybody then thought that the malaria of Rome was carried into the city from the coast marshes, it was supposed that this state of things was irremediable. We opposed to this view the fact of the salubrity of the Viminal, which is situated between the Esquiline and the Quirinal, and which ought to be as unhealthy as the two other hills were the malaria of the latter imported into the city instead of being indigenous. Believing it to be indigenous, we hoped that by shielding the surface of these hills from the direct action of the air (by building houses and paving the streets), the malaria would cease to be produced there. That is precisely what has happened, for the new quarters are very healthy. But the malaria is only held in abeyance, and is not definitely overcome; for if an extensive excavation is made in these hills, and the contact of the air with the malarious soil is thus re-established, during a hot and damp season, the production of malaria commences anew. A complete atmospheric purification is nevertheless the most stable of all the methods of obtaining a suspension of malarial production, but unfortunately its realization is very limited, for it is restricted to inhabited localities and to sodded surfaces.

The ideal method of insuring freedom from malaria should be to obtain a permanent immunity, that is, to be able to modify the composition of the infected soil in such a way as to make it sterile as regards malaria, without taking from it the power of furnishing products useful for the social economy. But all the elements indispensable for obtaining such a result fail us utterly just here. We do not yet know what ought to be, in general terms, the composition of a soil incapable of producing malaria, yet retaining those properties which are suitable for vegetation. When we shall have arrived at this first stage, there will still be a long road to travel; and the most difficult part will be to discover a practical means of imparting this salutary composition to all the numerous varieties of malarious soils.

Scientifically, then, in the present state of our knowledge we are unable to affirm anything on this point. Practically, we are not much further advanced. It is very probable that the combination of hydraulic purification with a forced cultivation of the soil has sometimes determined changes in its composition by which it has been rendered sterile as regards malaria. If that has happened, it has happened by chance, and we are unable to reproduce the result at will; for we have not all the data which might enable us to understand how it has come about. Most of the purifications obtained in ancient times, by means of forced cultivation, continued during centuries, have not been definite at all, but the production of malaria has been simply suspended. Hardly was the regular cultivation of the fields interrupted than the production of malaria recommenced. Among the numerous examples that I might cite in this connection, I will limit myself to that of the Roman Campagna. This seemed to have been made permanently healthy under the Antonii, but after the fall of the empire it began again to produce malaria, as if the forced cultivation through so many centuries had never been.

One might, strictly speaking, be content with such a result, and boldly undertake forced cultivation of all malarious districts, without stopping to ascertain whether the freedom from malaria so obtained would be definite, or whether the production of the poison were only suspended. Unfortunately, one is never sure of arriving at such a result, and no one can say, a priori, whether the forced cultivation of a given malarious tract will render it healthful. It must always be remembered that the first effect of forced cultivation, which requires an overturning of the soil by means of the plow, the spade, and the pick, is an unfortunate one, from a hygienic point of view, whenever we have to deal with a malarious country. Experience has shown, especially in Italy and America, that this overturning of the soil almost invariably increases the local production of malaria. And this can be readily understood, since the plowing and the digging in a soil containing the specific ferment increase the extent of surface of the ground in immediate contact with the atmosphere. This first mischievous effect is often gradually weakened by the continued cultivation, and may end by disappearing. At other times, on the contrary, it persists obstinately, and one is often forced in desperation to the resolve to level the ground again and to varnish it, so to speak, with a thick sowing of grass, if he wishes to suspend or weaken the malarial production.

However, when the local conditions will permit, it is well to try whether, by means of forced cultivation of the soil, it may not be possible to increase the efficacy of the hydraulic method of procuring immunity from malaria, or of the hydraulico-atmospheric method of "overlaying." The moment that it is known that this cultivation has frequently been advantageous, there comes forward a crowd of social reasons which induce us to attempt it, even though we be persuaded that we are about to engage in a game of chance. But to dare to attempt it is not all that is necessary; we need also the possibility of so doing, and just here we find ourselves in a vicious circle from which it is not easy to emerge. Forced cultivation cannot be accomplished without the presence of agriculturists in the region during the entire year; and the agriculturists cannot remain in the region during the fever season, for they run thereby too great a risk. For the solution of this question there is but one means: try to increase the power of resistance of the human organism to the attacks of the malaria. It is to a search after the means of accomplishing this result that I have devoted myself during the past few years.

There is nothing to hope for, as regards malaria, in acclimation. Individual acclimation is, and always has been, impossible. The malarial infection is not one of those a first attack of which confers immunity from other attacks. It is, on the contrary, a progressive infection, the duration of which is indeterminate, and which is of such a nature that a single attack may suffice to ruin the constitution for life. Collective or racial acclimation certainly existed in the past, at a time when specific remedies for pernicious malaria were unknown; and even later, when the employment of these remedies was very limited. The acclimation was due to a natural selection made by the malaria upon successive generations, from which it took away, almost without opposition, all those who possessed but a feeble individual power of resistance to the specific poison, while it spared those who possessed this power of resistance in an extraordinary degree. The first were, according to the Grecian myth, the human victims destined to appease the monster or demon who opposed the violation of the territory over which he had up to that time exercised an absolute sovereignty. The second became the founders of the race, and through them, from generation to generation, the collective power of resistance to the malaria was progressively increased. In our own days a like selection may take place among barbarous races, as it does among the cattle and the horses in a malarious region, but it has become an impossibility among civilized nations. By means of the specific remedies which we possess, the use of which is now so general, the lives of a large number of individuals whose resisting powers are very feeble are preserved; and these individuals beget others whose power of resistance to the action of the specific poison is still more feeble. This results after a number of generations in the physical degradation of that part of the human race which inhabits malarious countries.

We cannot, therefore, in the future, count upon the assistance of external natural forces to increase the power of resistance of human society against the assaults of malaria. Such an object can be obtained only by artificial means. It has been sought to attain this end by the daily administration of the salts of quinine, of the salicylates, and of the tincture of eucalyptus, each and every one tried in turn. But the salts of quinine are dear, exercise a prompt, though very transient anti-malarial action, and, when administered for a long time, disturb rather seriously the functions of the digestive and nervous systems. The salicylates, when well prepared, are rather dear, and there is as yet no proof that they possess prophylactic powers against malaria. The alcoholic tincture of eucalyptus is useful in malarious regions (as are all the alcoholics, beginning with wine) in quickening the circulation of the blood; may it, perhaps, also act as a preservative against light attacks of malaria? Possibly. But it is very certain that it possesses no efficacy in places where malaria is severe. It will suffice to prove this to recall the two epidemics of fever which afflicted the colony of the Tre Fontaine, near Rome, in 1880 and 1882. Everybody was attacked, and there were several cases of pernicious fever, although a good preparation of eucalyptus is manufactured in the place and is distributed largely to the colonists during the dangerous season of the year.

ARSENIC FOR MALARIA.

Having several times had occasion to observe, in malarious regions, that when recourse was had to arsenic in order to subdue fevers over which quinine had exerted almost no effect, relapses occurred but rarely; and having been able to satisfy myself that the arsenical treatment sometimes procured a permanent, immunity in individuals who are subject to frequent attacks of malaria, I began in 1880 to employ arsenic (arsenious acid) as a prophylactic in certain portions of the Roman Campagna. This remedy was indicated in an experiment of this sort, not only by reason of its durable anti-malarialae effects, but also by its low price, by the beneficial influence it exerts upon all the nutritive functions, and because it has no disagreeable taste and may therefore be given to everybody, even to children. My first trials in 1880 were rather encouraging, and I felt myself justified in engaging some proprietors and the association of our southern railroads to repeat the experiments on a large scale the following year, recommending them, however, to use arsenic in a solid form as offering an easy and certain dosage. This extensive prophylactic experiment began in 1881, and acquired constantly increasing proportions in 1882 and 1883, which have become still larger this year. An experiment of this kind is not easy to conduct in the beginning. The name, arsenic, frightens not only those whom we desire to submit to its action, but also the physicians, whose exaggerated fears have sometimes rendered the experiments of no avail, since they were conducted too timidly and the doses of arsenic employed were altogether insufficient. But some intelligent men, especially M. Ricchi, physician in chief to the southern railroads, were able speedily to triumph over these obstacles, and to place the experiment on a firm basis. The general testimony of all the facts which they have collected tends really to prove that when the administration of arsenic is begun some weeks before the presumed season for the appearance of the fever, and when it is continued regularly throughout the whole of this season, the power of resistance of the human organism to malaria is increased. Many individuals gained thereby a complete immunity, others a partial immunity, that is to say, they were sometimes attacked by the fever, but it never, even in very malarious districts, assumed a pernicious form, and was easily subdued by very moderate doses of quinine. Last year, for example, in the district of Borino, where the malaria is very severe, M. Ricchi experimented upon seventy-eight employes of the southern railroads, dividing them into two equal divisions, one of which received no prophylactic treatment, while the other was submitted to a systematic arsenical treatment. At the end of the fever season it was found that several employes among the first half had been attacked by fevers of a severe type; while thirty-six of those in the second division had enjoyed a complete immunity, the three others having been attacked, but so lightly that they cured themselves by quinine without seeking medical aid.

Facts of this sort are very encouraging, and the more so as the general health of those submitted to the prophylactic treatment was much improved. It was found almost invariably, upon the termination of the experiment, that there had been an increase in bodily weight and an amelioration of the anaemia which is so common in milarious districts. But, in order to arrive at such results, it is necessary to be at once bold and prudent. On the one hand, it is necessary to graduate very carefully the daily dose, never exceeding at the commencement the dose of two milligrammes (3/100 grain per diem) for adults, and never giving the arsenic upon an empty stomach. On the other hand, it is necessary to gradually push the dose up to ten or twelve milligrammes (15/100 or 18/100) a day for adults, in districts where the malaria is very severe, giving the arsenic in such a way that there is never an accumulation of the drug in the stomach. Most of the experiments which have been undertaken this year are being conducted on this plan, and there is reason to hope that they will give satisfactory results.

We must not, however, rest here if we wish to attain promptly the end proposed, namely, that of planting colonies in malarious districts without exposing the colonists to grave danger. Even if we realize perfectly the hope which I conceived in 1880, and if we are enabled to prove that arsenic increases man's power of resistance to the assaults of malaria, we must not imagine that everything is accomplished. It will take a long time before the use of a preservative method of this kind becomes generalized; we have first to contend against the fear which nearly every one experiences when arsenic is mentioned, and then there will also be difficulty in establishing everywhere a proper control over its administration. In every attempt at the colonization of malarious regions it will be necessary to combat for a long time the diseases caused by malaria, and we must seek for a method of combating them by a means which is in the possession of everybody, and which shall not be dangerous to the general economy of the human organism. Those who do not know from actual experience the miseries of a malarious country, think only of combating the acute forms of infection, which often place the patient in danger of death. But this danger, though great, is for the most part imaginary, provided that assistance be obtained in time. But that which desolates families, and which causes a physical degradation of the human race exposed to the attacks of malaria, is the chronic poisoning, which undermines the springs of life and produces a slow but progressive anaemia. This infection often resists all human therapeutic measures, and is even aggravated by the use of quinine, which is given during the recurrent paroxysms of fever. Quinine is, when given for a long period of time, a true poison to the vaso-motor nerves. The question, then, is to replace quinine, and the alkaloids which possess an analogous physiological action, by an agent the efficacy of which against, chronic malarial poisoning may be greater and the dangers of its employment less.

THE LEMON FOR MALARIA.

A happy chance has led Dr. Magliori to the discovery of an agent of this sort which was traditionally in use by certain Italian families. It is an exceedingly simple thing—merely a decoction of lemon. It is prepared by cutting up one lemon, peel and all, into thin slices, which are then put into three glassfuls of water and the whole boiled down to one glassful. It is then strained through linen, squeezing the remains of the boiled lemon, and set aside for some hours to cool. The whole amount of the liquid is then taken fasting. It is well known that in Italy, Greece, and North Africa, they often use lemon juice or a decoction of lemon seeds, as a remedy in malarial fevers of moderate intensity; and in Guadaloupe they use for the same purpose a decoction of the bark of the roots of the lemon tree. All these popular practices tend to show that the lemon tree produces a febrifuge substance, which resides in all parts of the plant, but which would seem to be most abundant in the fruit. In fact, among the popular remedies employed against malarial infection, that which I have just described is the most efficacious, for it can be employed with good effects in acute fevers. But it is especially advantageous in combating the chronic infection, which is rebellious to the action of quinine, and in removing or moderating its deplorable effects.

Hardly had I learned of this method of medication, when I hastened to induce some proprietors in the Roman Campagna to try it with their farm hands; and, after witnessing the good results there, I endeavored to persuade practitioners to make a trial of the same treatment. I was ridiculed a little at first, for they thought it rather singular that a professor should be trying to popularize on old woman's remedy. In reply to that I answered that practical medicine would not have existed, had it not known how to treasure up from age to age the facts of popular experience; and I ventured to remark that, had the Countess de Chinchon waited until methodical researches had been made into the physiological action of cinchona bark, before popularizing the remedy, the use of which she had learned from the semi-barbarous Peruvians, in all probability humanity would still, as regards malaria, be dependent upon the medication practiced in the middle ages. Happily these arguments had the desired effect upon certain distinguished practitioners, some of whom, especially in Sicily and Tuscany, have already collected together a tolerably large number of very encouraging observations. One of them, Dr. Mascagni, of Avezzo, tried the remedy in his own person, and succeeded in promptly curing an obstinate malarial fever which had resisted the action of quinine.

Gentlemen, in dealing with malaria we ought always to hold popular experience in high esteem, for we owe much to it. We owe to it the fact that we have been liberated from the paludal idea, and furthermore, that we have learned that it is often better, instead of trying to prevent the importation, for the most part imaginary, of malaria from distant marshes, to suppress its production in the soil under our feet or in that immediately surrounding us. We owe to it the knowledge, which we now have, that malaria rises up into the atmosphere only to a limited height, so that by placing ourselves a little above this limit in order to eliminate the possibility of the malaria being carried up to us by oblique atmospheric currents, we are enabled to breathe an air which does not contain this ferment, or which contains it only in insignificant amounts; thus one may even sleep in the open air during the night in very unhealthy districts without running any risks. The knowledge of this fact has led some peoples of Greece, and the inhabitants of the Pontine Marshes, to sleep in the open air on platforms raised on poles four or five meters (twelve to fifteen feet) in height. Some people in the Roman Campagna have built houses for themselves on top of the ancient tombs, the walls of which are perpendicular; the American Indians fasten their hammocks as high up as possible to the trees of the malarious forests; and very recently, the engineers of the Panama Railroad had little wooden huts built in the trees in order to procure safety against the terrible outbreak of malaria which occurred during the construction of that iron way. We owe, finally, to this popular experience the discovery of the specific action of quinine, and the consequent preservation of thousands and thousands of human lives. Why should we reject a priori and without investigation other useful data which it may yet present to our consideration? If we wish to make progress in this question of rendering malarious countries healthy, we must always hold before our eyes a double object—to find a means of prophylaxis which may be accessible to everybody; and, at the same time, to find a means equally within everybody's reach, to overcome chronic malarial poisoning and its evil consequences. Science is still too far behind to permit us to hope that we shall soon succeed in discovering this second means by purely scientific researches. We ought, therefore, to gather together with great care all the facts which point to the possibility of a solution of this problem, and if the measures to which these facts point seem to be incapable of doing harm, we ought to try them boldly, and not be restrained by a false idea of the dignity of science. The social importance of the problem is too great to allow of its solution being retarded by the fear that scientific men may be accused of having been outrun by the ignorant. True science has none of these puerile susceptibilities; on the contrary, it deems it an honor to be able to seize all the observations of fact, whoever may have been their first recorder, to put them to the crucial test of methodical experiment, and to convert them into a new stepping stone on the march of human progress.

* * * * *



HALESIA HISPIDA.



This fine hardy shrub is perhaps best known under the name of Pterostyrax, but we think gardeners will, quite independently of botanical grounds, be inclined to thank Messrs. Bentham and Hooker for reducing the genus to the more easily remembered name of Halesia. Halesia hispida is a hardy Japanese shrub of recent introduction, with numerous white Deutzia-like flowers in long terminal racemes. A peculiar appearance is produced by the arrangement of the flowers on one side only of the branchlets of the inflorescence. The botanical history of the plant is well known, and our illustration is sufficient to show the general appearance of the plant. It is decidedly one of the best recent additions to the number of hardy deciduous flowering shrubs. For the specimen whence our figure was taken we are indebted to W.E. Gumbleton, Esq.—The Gardeners' Chronicle.

* * * * *



WINDFLOWERS.



The genus Anemone has a great future. Even at present its popularity is only a little less than that of roses and daffodils, but when we trust to seeds as a means of reproducing the best of windflowers instead of buying dried roots from the shops, then, and then only, will "coy anemone" become a garden queen. A. coronaria, if treated as an annual, furnishes glowing blossoms from October until June, after which A. dichotoma and A. japonica in all its forms—white and rosy—carry on the supply and complete the cycle of a year's blossoming. By sowing good, newly-saved seed in succession from February until May in prepared beds out of doors, the common crown anemone may in many sunny, sheltered gardens be had in bloom all the year round. This is saying a great deal, but it is true; indeed, it is questionable if we have any other popular garden flower which is at once so showy, so hardy, and so continuous in its blossoming. A friend beside me says: "Ah! but what of violas?" To which I reply: "Grow both in quantity, since both are as variable as they are beautiful." But when viola shrinks in foggy November from the frost demon, anemone rises Phoenix-like responsive to the first ray of sunshine. Besides, fair Viola, richly as she dresses in velvet purple or in golden sheen, has not yet donned that vivid scarlet robe which Queen Anemone weareth, nor are her wrappers of celestial azure so pure; and blue is, as we all know, the highest note of coloring in floral music. But comparisons are not required, Anemones are variable and beautiful enough to be grown for themselves alone. No matter whether we look at a waving mass of sparkling windflowers in a vineyard or cornfield by the Mediterranean, or walk knee deep among the silvery stars of A. nemorosa in an English wood—"silvery stars in a sea of bluebells"—they are alike satisfying. I believe that there is any amount of raw material in the genus Anemone—hardihood, good form and habit, and coloring alike delicate and brilliant; and what we now want is that amateurs should grow them with the attention and care that have been lavished upon roses and lilies and daffodils. But, alas! we have some capricious beauties in this group. A. coronaria and some other species succeed well treated as seedling hardy annuals, and others, as A. apennina, A. Robinsoni, A. Pulsatilla, A. dichotoma, and A. japonica, may be multiplied ad infinitum by cuttings of the root. It is when we come to the aristocratic Alpine forms, to A. alpina, A. sulphurea, A. narcissiflora, etc., that difficulties alike of propagation and of culture test our skill to the uttermost. Tourists fond of gardens walk over these plants in bloom every year; they dig up roots and send them home; but they are as yet very rare in even the best of gardens. Nor is it easy to rear them from seeds. A year ago I sowed seed by the ounce each of A. alpina and of A. sulphurea, but as yet not a single plantlet has rewarded me for my trouble. Even freshly gathered seeds of A. narcissiflora will not germinate with me, but I live in hopes of surmounting little difficulties of this kind, and in the mean time, perhaps, others more fortunate will tell us how to amend our unsuccessful ways. One of the prettiest species which is now in flower in our gardens is the pure white A. dichotoma, which carries on the succession after the Snowdrop anemone (A. sylvestris) has passed away. Then we have dreams, and lend willing ears to the oral traditions of Anemone alba. Is this species in cultivation, or where may a figure of it be seen? It is said to be of neat habit, 12 inches high, with erect, saucer-shaped, white blossoms 3 inches in diameter. The species we now figure is well worth a place, being easily raised from seeds. It is called Anemone decapetala, and if not by any means a showy species, tufts of it three years from seed have this season been very pretty. It grows less than a foot in height, and bears pale creamy yellow flowers the size of a shilling on branched flowering stems; each blossom has eight or nine sepals around a yellowish green center. Some of our clumps had from a dozen to twenty flowers open at the same time, and the general effect in the early morning sunshine is a very pretty one. We have another species similar in habit which is just now a mass of rosy buds, and if you blow open its sepals, they are of a bright magenta color inside, but I never yet saw a flower open naturally on this plant. Just as the sepals open at the tips, and you think they are about to expand, they shrivel and fall away, leaving a tuft of greenish yellow stamens in the center. Is it A. Hudsoni? Another species not often seen, but well worth culture, is A. coerulea, a kind with finely cut leaves and purplish blue flowers. Then A. coronaria, The Bride, a pure creamy white kind, with flowers 3 inches across, raised by Van Velsen, of Haarlem, is really a good addition to these dainty blossoms, and affords a vivid contrast to the fiery A. fulgens. I have received this year some roots of anemones, iris, and other hardy flowers from the site of ancient Troy, and trust that some of these, if not new, will be beautiful additions to our gardens. The true A. vitifolia from northern India does well in mild localities; but best of all of this perennial large-leaved race is A. japonica alba, the queen of all autumnal kinds, rivaling the best of all hardy border flowers in purity and freedom of blossoming. Taken as a class, windflowers are so beautiful that we cannot grow them too plentifully, and but few other genera will so well repay cultural attention at all seasons.—F.W.B., in The Garden.

* * * * *



STORY OF LIEUT. GREELY'S RECOVERY.

The story of Lieut. Greely's recovery after his rescue from Cape Sabine is given by Passed Assistant Surgeon Edward H. Green, U.S.N, of the relief ship Thetis, in a communication to the Medical Record. The cases of Greely's six fellow survivors, it is remarked, were very similar to his. The condition of all was so desperate that a delay of two hours in the camp was necessary before they could be removed to the relief vessels. Brandy, milk, and beef essence were administered.

Lieut. Greely's disease is called by the surgeon asthenia, a diminution of the vital forces. Greely fainted after being carried to the wardroom of the Thetis. When he was brought to, a teaspoonful of minced raw fresh beef was given to him. His clothes were carefully cut off of him, and heavy red flannels, previously warmed, were-substituted. He was excessively enacted, and his body emitted an offensive odor. His skin hung from his limbs in flaps. His face, hands, and scalp were black with a thick crust of soot and dirt. He had not washed himself or changed his clothing for ten months. He had lived a long time at a temperature inside the hut of from five to ten degrees above zero. He was nervous and irritable, at times almost irrational, and his eyes were wild and staring. He insisted on talking, craving news, and demanding food, but he complained of no pain.

His tongue was dry and cracked, and coated a brownish black. He was ravenously hungry. His pulse was 52, and soft or compressible. His skin was cold, clammy, shriveled, and sallow. His temperature under the tongue was 97.2 deg. There was great muscular waste, and he was unable to move or to stand without support. Before leaving Fort Conger in August, 1883, he weighed 168 pounds. He now weighed 120 pounds. He was carried aboard the Thetis about 11 P.M. on June 22, it being then broad daylight in that region, and his treatment from that hour until 8 o'clock the next morning was a teaspoonful of minced raw beef, alternated every half hour with a teaspoonful of milk punch. Strict quiet was enjoined.

On June 23 Surgeon Green was compelled to allow him to read some letters from home, after which he seemed less restless. He talked rationally, but showed a loss of memory in often repeating what he had previously said. He had not closed his eyes in sleep since his rescue. There was excessive constipation. The treatment was the same as during the night, except that finely cut raw onion was added to the minced beef, and half an ounce of milk punch was given every two hours.

On the next day, June 24, although he had yet had no sleep, and he showed a great desire to talk and read, there were signs of improvement. He was less persistent in demanding food, his tongue presented a moister appearance, he began to complain of soreness in his limbs, and his heart sounded stronger. Surgeon Green had him sponged with tepid water, and briskly rubbed with flannels. He gave him a small quantity of oatmeal thoroughly boiled, beef essence, and scraped beef and onion.

On the next day, June 25, Lieut. Greely slept for the first time. He awoke after two or three hours, much refreshed. He talked without excitement, and his tongue and skin began to look more natural. His muscles felt sore, and his ankles were puffed.

On the next day, June 26, his mind was tranquil, but there was a loss of memory of words. He was allowed to sit up in bed and read a little. He slept six hours. For the first time since his rescue medicine was given him—some muriate of iron.

On the next morning he got eight ounces of broiled steak and on the following day, June 28, he dressed himself and sat up for two hours. His food was now gradually increased from day to day, and he continued steadily to improve. On July 1 he was well bundled up, and allowed to sit on deck for an hour in the sunshine. On July 17, the Thetis arrived at St. Johns.

Lieut. Greely's muscles were now filling out rapidly, and he was allowed to go on shore and take exercise. Here, Surgeon Green says, the lieutenant committed an error in diet at the American Consul's table, and suffered for two days with a slight attack of intestinal indigestion. On July 25, for the first time, he was allowed to eat three square meals. Six weeks after his rescue he had gained 49 pounds. He gained 91/2 pounds the first week, 15 pounds the second week, 8 pounds the third week, 7 pounds the fourth week, 51/2 pounds the fifth week, and 4 pounds the sixth week. Surgeon Green adds, under the head of "remarks":

"Vital depression, as exhibited by the temperature, not marked; digestion fairly good all the time; nervous system soon calmed. Microscopic examination of blood disappointing; exhibiting no unhealthy character of red blood globules. Liver not secreting. Large gain in weight, due to rapid assimilation of food, owing to a great muscular waste."

* * * * *



THE CAY MONUMENT AT UXMAL.

DISCOVERED BY DR. LE PLONGEON ON JUNE 1, 1881.

In 1881, we went for the second time to the ancient ruined city of Uxmal, Yucatan, and lived there four months, making moulds of every ornament and inscription, from which moulds perfect facsimiles of those grand old palaces can be produced in plaster, and placed in any exposition or museum.

During our stay there, on June 1, Dr. Le Plongeon had the great satisfaction of discovering a monument, a splendid work of art in all its pristine beauty, fresh as when the artist put the finishing touch to it, without blemish, unharmed by time, and not even looked upon by man since it was concealed, ages ago, where Dr. Le Plongeon discovered it through his interpretations of certain inscriptions. It was probably hidden to save it from destruction, between the sixth and seventh centuries of the Christian era, when the Naualts invaded and overran the country, demolishing many art treasures of the Mayas.



The monument represents a mastodon head, with various ornaments above and below it, the whole measuring 3.50 m. (11 feet 41/2 inches) in height, and in width 1.25 m. (4 feet 1 inch). Above the mastodon head there is a chain, nearly 10 inches deep; the stones forming the links are sculptured and fitted into each other just like the rattles of a rattlesnake; and yet higher another row of stones resembling knots. The uppermost part is composed of stones that incline outward from above; they are flat, measuring 0.55 by 0.45 centimeters (21 inches by 17 inches), and are covered with various signs pertaining to certain mysteries.

On the sides of the mastodon's trunk are these signs



which read Tza, and means that which is necessary. Beneath the trunk and the upper jaw is what is meant to represent the distended jaws of a serpent; on it is inscribed the family name, , Can, the mouth (chi) of the serpent giving the second part of the name. Canchi means "serpent's mouth," and was the name of the royal family that ruled over the Mayas when their civilization was at its height.

Within the serpent's jaws is the greatest gem of American sculpture yet discovered. It is a head and throat, sculptured in the round, of Cay Canchi, the high priest and elder brother of the warrior Chaacmol, whose statue we exhumed from 8 meters below the soil in Chichen Itza, during the year 1876; which statue was afterward robbed from us by the Mexican government, and is now in the museum at Mexico city. The stone out of which the beautiful head is cut is not polished, but wrought so finely as to almost imitate the texture of the skin. It is decidedly a good looking face. The nostrils are most delicately chiseled, and the cartilage pierced; the eyes are open, and clearly marked. On the right cheek is his totem, a fish traced in exceedingly small cross bars. The forehead is well formed, not retreating, and incircled by a diadem composed of small disks, from the front of which projects a perfect fish's head. The hair is short in front, and hangs like a fringe on the upper part of the forehead, but is longer at the sides, hanging in straight locks.

On the wall against which this monument is built, feathers are sculptured, forming a canopy. Such a superb chef d'oeuvre proves beyond doubt that the Maya artists were in no way inferior to those of Assyria and Egypt.

Having been so unjustly deprived of Chaacmol without any remuneration for our time, labor, and expenditure, we decided to save the Cay monument from destruction at any cost, for should any ignorant persons attempt to move it, they would break it in so doing; so, after making a mould of it, we guarded it most securely, as we considered best, afterward inclosing it with planks, then built it up and left it as we had found it.

Sr. Don Romero Ancona, then Governor of Yucatan, was very much provoked because we would not reveal the whereabouts of our find, but gained nothing by it, and the beautiful monument is still safe.

ALICE D. LE PLONGEON.

* * * * *

Rolled gold is made by casting an ingot of brass, and while this is still hot pouring upon it a thin layer of gold alloy. The ingot when cold is forced between steel rollers until a long, thin ribbon is produced, of which the proportion of gold and brass is the same as of the ingot. The percentage of gold is reduced as low as two and three per cent. This rolled gold is used in making cheap bracelets and watch chains. It wears from one to ten years.

A CATALOGUE, containing brief notices of many important scientific papers heretofore published in the SUPPLEMENT, may be had gratis at this office.

* * * * *



The Scientific American Supplement.

PUBLISHED WEEKLY.

TERMS OF SUBSCRIPTION, $5 A YEAR.

Sent by mail, postage prepaid, to subscribers in any part of the United States or Canada. Six dollars a year, sent, prepaid, to any foreign country.

All the back numbers of THE SUPPLEMENT, from the commencement, January 1, 1876, can be had. Price, 10 cents each.

All the back volumes of THE SUPPLEMENT can likewise be supplied. Two volumes are issued yearly. Price of each volume, $2.50, stitched in paper, or $3.50, bound in stiff covers.

COMBINED RATES—One copy of SCIENTIFIC AMERICAN and one copy of SCIENTIFIC AMERICAN SUPPLEMENT, one year, postpaid, $7.00.

A liberal discount to booksellers, news agents, and canvassers.

MUNN & CO., PUBLISHERS,

261 BROADWAY, NEW YORK, N.Y.

* * * * *



PATENTS.

In connection with the SCIENTIFIC AMERICAN, Messrs. MUNN & Co. are Solicitors of American and Foreign Patents, have had 38 years' experience, and now have the largest establishment in the world. Patents are obtained on the best terms.

A special notice is made in the SCIENTIFIC AMERICAN of all Inventions patented through this Agency, with the name and residence of the Patentee. By the immense circulation thus given, public attention is directed to the merits of the new patent, and sales or introduction often easily effected.

Any person who has made a new discovery or invention can ascertain, free of charge, whether a patent can probably be obtained, by writing to MUNN & Co.

We also send free our Hand Book about the Patent Laws, Patents, Caveats. Trade Marks, their costs, and how procured. Address

MUNN & CO., 261 BROADWAY, NEW YORK.

Branch Office, cor. F and 7th Sts., Washington, D.C.

THE END