Chapter II: Part 2

Apparently a new plague focus, independent of that in Yunnan and Hong Kong, has been recently discovered in Manchuria. The plague seems to have existed in this province for more than ten years under the name of Tarabagan plague, and is believed to be spread by a rodent, the Arctomis cobuc, which is subject to a hemorrhagic pneumonia. The presence of such an independent endemic focus in Manchuria indicates the possibility of the spread of the disease by caravan to Lake Baikal, and thence by the Siberian railroad to Russia. Indeed, the epidemic of pneumonic type which began July, 1899, at Kolobovka, in Astrakhan, while it may have been imported from Persia, might also owe its origin to the Mongolian focus.

Russia, however, is not the only country endangered by the overland transmission of the disease. There are commercial highways which lead from Northwestern India through Baluchistan and Persia to the Caucasus, and through Turkey to Constantinople. Grave danger threatens from this source, and more especially from the cities along the Persian Gulf. Two important cities here are already infected, namely, Bushire, in Persia, and Bassorah on the Tigris, in Turkey. It would appear as if Turkey and Persia would escape with difficulty from a visitation of this dread disease.

Such, then, is the geographical distribution of the present outbreak of the plague. This, an apparently extinct disease, has suddenly reappeared and given evidence of its power to spread death and desolation. Fortunately, however, modern sanitary precautions are quite able to restrict its progress, provided they be applied at the proper time and place. Filth and overcrowding, protracted wars and famine, have been the powerful allies of the plague in the past. Through their aid this disease has made a deep impression upon the pages of history. It may not be out of place, therefore, to turn from the present outbreak of the disease and trace its grewsome past.

In ancient writings references are found which would seem to indicate the existence of the plague at a very early date. The Bible contains several such references (Deuteronomy, Chapter 28, paragraph 27. Samuel I, Chapter 5, paragraphs 6, 9). The latter especially deals with the plague which attacked the Philistines after they took the ark. The rôle of rats in the dissemination of the disease is, as some believe, apparently referred to in the trespass offering of “five golden emerods and five golden mice.” The return of the ark, together with this trespass offering, brought also the plague, “because they had looked into the ark of the Lord, even he smote of the people fifty thousand and threescore and ten men.” Poussin’s painting of this Philistine plague, exhibited in the Louvre, shows several dead rats on the streets. It is evident that the susceptibility of the rat to the plague had been noticed even at this early date. The plague of boils visited upon the Egyptians as related in Exodus (Chapter 9, paragraphs 9 and 10) has also been taken to indicate the pest of today, but neither of these scriptural references can be said to be sufficiently definite.

The Attic plague, which ravaged the Peloponnesus 430 years before Christ, has been accurately described by an eye-witness, the historian Thucydides. His narration may be considered the earliest exact record of an epidemic. Like all the great epidemics of subsequent ages, it was ushered in by the overcrowding, the misery and the famine consequent upon prolonged wars. The combustible material was there, and all that necessary was the spark to begin the work of death and devastation. It is noteworthy that the origin of the pest was traced by Thucydides to Egypt or Ethiopia, from whence it spread gradually overland to Asia Minor and thence by boat to Athens. The nature of this first great historic epidemic is and will remain uncertain. There are those who consider the Attic pestilence as one of bubonic plague, but the fact that in the very careful description of the disease no mention is made of buboes and the statement that death occurred from the seventh to the ninth day would indicate that the disease was something else. Buboes are characteristic, it is true, of the plague, but it should be remembered that outbreaks of the pneumonic form, with little or no glandular enlargement are not uncommon. Death, however, in the case of plague is very common on the second or third day, and is less liable to occur in more protracted cases. These facts lead to the commonly accepted belief that the Attic pest was not the bubonic plague. It may have been typhus fever, possibly smallpox.

The great pestilence which devastated Rome and its dependencies in 166, Anno Domini, is known as the plague of Antoninus or of Galen. This prolonged epidemic was brought to Rome by the returning legions from Seleucia. It was not characterized by buboes, and it is very probable that it was largely smallpox. On the other hand, the plague of Saint Cyprian, which prevailed from 251 to 266 Anno Domini, may have been partly bubonic in nature, since, it prevailed during the fall and winter months and ceased during the hot summer. The disease was said to be communicated by means of clothing and by the look. It spread from Ethiopia to Egypt and thence through the known world.

Although the above early epidemics cannot be identified with the bubonic plague, there is nevertheless excellent evidence of the existence of this disease in remote antiquity. The first undoubted testimony on this point is that furnished by Rufus of Ephesus, who lived in the first century of the Christian era. The writings of this author are no longer extant, but they are quoted by Oribasius, the physician and friend of Julian the Apostate, who lived in the fourth century. The writings of Oribasius were discovered in the Vatican Library and were published early in this century by Cardinal Mai. In the forty-fourth “Book of Oribasius” occurs the extract taken from Rufus of Ephesus, from which it appears that “the so-called pestilential buboes are all fatal and have a very acute course, especially when observed in Libya, Egypt and in Syria. Dionysius mentions it. Dioscorides and Posidonius have described it at length in their treatise upon the plague which prevailed during their time in Libya.” The description which then follows of the buboes and of the disease is an exact counterpart of the present plague. The writings of the authors quoted by Rufus are no longer extant, but one thing is certain, and that is that the Dionysius referred to lived not later than 300 years before Christ. The other two physicians lived in Alexandria contemporaneous with the birth of Christ. It may, therefore, be considered as an established fact that the plague existed in Egypt, Libya and Syria as early as 300 years before Christ. This is of especial interest in view of the recent discovery by Koch of an endemic plague focus in British Uganda and German Kisiba, at the headwaters of the Nile. Whether it ever invaded European territory prior to the sixth century is unknown.

The great plague of Justinian which broke out in 542, Anno Domini, appeared first in Egypt, and from thence it spread east and west throughout the known world and persisted for more than a half century. So unknown was the plague in Europe at that time that the physicians of Constantinople considered it a new disease. Procopius, who was an eye-witness of the plague at Constantinople, states that the daily mortality in that city was at times over 10,000.

The pandemic of Justinian resulted in the distribution of the plague for the first time throughout the length and breadth of known Europe. From that time on the early chroniclers make repeated mention of devastating plagues consequent upon the miseries of war and famine. The descriptions of these pestilences are, as a rule, insufficient to identify them with the bubonic plague. Typhus, scurvy, smallpox and other diseases undoubtedly alternated in the work of destruction. Of the scores of epidemics thus recorded during the eight centuries following this first visitation few, indeed, can be identified to a certainty with the bubonic plague, and yet there can be no doubt but that this disease occupied no second rank during the dreary darkness of the middle ages. This era in history may be said to have been ushered in by the Justinian plague, and it was closed by an even more disastrous outbreak of this same disease. All the ravages and slaughter consequent upon the great historic battles, when taken together, pale into insignificance on comparison with that dread visitation of the fourteenth century, the ‘black death’.

It is noteworthy that this great historic epidemic did not originate in Egypt, as did many of its predecessors. Without exception the contemporaneous writers ascribe its origin to Cathay, or the China of today. This fact is of interest when it is borne in mind that at the present time we know of the existence of two endemic foci in China, besides that of Gurhwal in India, of Beni Cheir in Arabia and of Uganda and Kisiba in Africa. Whatever may have been its source, the fact is that it advanced from the Orient along the three principal routes of travel. One of these led from the Persian Gulf through Bassorah and Bagdad along the Euphrates, across Arabia to Egypt and Northern Africa. Another route passed from India through Afghanistan, and skirting the southern borders of the Caspian and Black Seas, eventually reached Asia Minor. A third route from Turkestan and China led around the northern shore of the Caspian Sea to Crimea, and thence to Constantinople. It was along these several routes that the plague advanced and spread over most of Western Asia and Northern Africa.

The European black death, however, can be traced with accuracy to the Crimean peninsula. Gaffa, a town in Crimea, now known as Theodosia, had been founded and fortified by the Genoese. It, as well as other cities along the Black Sea, was largely populated by Italians. One of these, Gabriel de Mussis, a lawyer in Gaffa, has left a faithful account of his experience and share in the introduction of the plague into Europe. In 1346 in the Orient numberless Tartars and Saracens were attacked with an unknown disease and sudden death. In the city of Tanais, through some excess, a racial struggle ensued between the Tartars and the Italian merchants. The latter eventually escaped and took refuge in Gaffa, which in time was besieged by the Tartars. During the siege, which lasted three years, the Tartar hordes were attacked by the plague, which daily carried off many thousands. The besiegers, despairing of reducing the city by direct attack, attempted to do so in another way. By means of their engines of war they projected the dead bodies into the beleaguered city, which, as a result, soon became infected. The Christian defenders took to their ships, and abandoning Gaffa, sailed westward, touching at Constantinople, Greece, Italy and France.

Wherever the infected vessels touched they left the plague. Constantinople thus became infected early in 1347. During the summer Greece, Sardinia, Corsica and parts of the Italian coast developed the disease. In the fall it reached Marseilles. The following year it spread inland into Italy, France, Spain, and even into England. In another year or two it spread over Germany, Russia, and crossed to the Scandinavian peninsula. Within four years it had completed the circuit of Europe, spreading untold death and misery. No greater catastrophe has been recorded in the history of the world.

The rapidity with which the disease spread among the fugitives from Gaffa, and in the cities visited by their ships, is despairingly narrated by De Mussis, who, returning in one of the ships to Genoa, says: “After landing we entered our homes. Inasmuch as a grave disease had befallen us, and of the thousands that journeyed with us scarcely ten remained, the relatives, friends and neighbors hastened to greet us. Woe to us who brought with us the darts of death, who scattered the deadly poison through the breath of our words.” According to this writer 40,000 died in Genoa, leaving scarcely a seventh of the original population. Venice was said to have lost 100,000, Naples 60,000, Sienna 70,000, Florence 100,000. All told, Italy lost half of its population.

Of the contemporaneous writers none has printed the horrors of the plague more vividly than does Boccaccio in his introduction to the ‘Decameron.’

“What magnificent dwellings, what notable palaces were then depopulated to the last person! What families extinct! What riches and vast possessions left, and no known heir to inherit! What numbers of both sexes in the prime and vigor of youth, whom in the morning either Galen, Hippocrates, or Æsculapius himself but would have declared in perfect health, after dining with their friends here have supped with their departed friends in the other world!”

From Marseilles the plague spread through Provence with disastrous results. In some monasteries not even a single survivor was left. In one of these Petrarch’s brother buried thirty-four of his companions. At Avignon, the seat of the Pope, 1,800 deaths occurred in three days. In Paris more than fifty thousand died of the plague.

In England the black death appeared in August, 1348, and continued till the autumn of 1349, when it disappeared. London, which at that time probably had a population of 45,000, had a mortality of about 20,000. No exact statement can be made of the relative mortality in England, although many undoubtedly extravagant guesses are recorded by contemporaneous writers.

It is estimated that the population of Europe previous to the outbreak of the black death was about one hundred and five millions. One quarter of the population, or about twenty-five millions, are said to have died of the plague. This may be but a mere estimate, it may be grossly inaccurate, but it nevertheless indicates the deadly character of the pestilence. According to a report made to Pope Clement VI, the total mortality for the known world was placed at forty-three millions. One-half the population of Italy succumbed. The Order of Minorites in Italy lost 300,000 members. The Order of Capuchins in Germany lost 126,000 members, while the total of deaths in Germany was placed at 1,200,000.

The invasion of Europe by the black death was sudden and rapid. The seeds of the disease, once planted on European soil, persisted, as might be expected, for no little time. Although the great epidemic was said to have lasted till 1360, it must not be inferred that it then ceased altogether. Diverse localities retained the infection, and, as a result, new outbreaks, though to a less extent, continued to outcrop during the following years. From that time on every decade or two witnessed more or less pronounced outbreaks of the disease in France, England and Italy. The chroniclers of those local outbreaks during the latter half of the fourteenth and during the entire fifteenth century did not always make it clear that the pestilence described was the real plague. It was but natural to include typhus and other diseases under the dreaded term of pest. Nevertheless, the frequency of these outbreaks indicates the persistence and the wide dissemination of the plague during those years.

During the sixteenth century the plague apparently began to show a decrease in its frequency, although during this period, as before, other epidemic diseases were mistaken for it. Germany, Holland, certain cities in France, and especially in Italy were scourged by the plague during this century. The noteworthy outbreak in Italy in 1575-77 was due to fresh importation from the Orient. The disease spread throughout Italy, and the devastation it caused was not inferior to that of the great plague two centuries before. For example, in 1576 in Venice 70,000 died of the disease.

During the seventeenth century the plague asserted itself with great severity. Following a famine, it prevailed in Russia in 1601-1603, and some idea of its destructiveness may be gained when it is stated that in Moscow alone 127,000 lives were taken. During the following decade even greater epidemics prevailed in Western Europe. France and England were invaded, and in Switzerland it even penetrated to the highest Alps. Basel in 1609-1611 had 4,000 deaths, while London in 1603 yielded 33,000.

The terrible epidemic which ravaged Northern Italy in 1629-1631 deserves more than a passing notice. During those years more than a million died of the disease. Scarcely a town in Northern Italy escaped. The city which, perhaps, suffered the most was Milan, where, in 1630, the deaths from all diseases are said to have amounted to 186,000. The Milan outbreak has been graphically described by Manzoni, in his celebrated ‘I Promessi Sposi.’ Unrecognized, the disease entered Milan in October, 1629. The mild cases which were met with during the winter months lulled the fears of the people and encouraged the mass of physicians to deny the existence of the plague. But in April the disease began to assert itself in terrible earnest. The frenzied populace, blind to the contagiousness of the disease, were possessed with the strange hallucination that obtained during former plague epidemics in other Italian cities, that the pest spread because of poison scattered about by evil-minded persons. Suspicious strangers were, as a result, stoned in the streets, imprisoned and even put to death by legal process because of such fanatical beliefs. To offset the growing pestilence, the people demanded of the Archbishop that a solemn religious procession be held, and that the holy relics of Saint Charles be exposed. At first this was refused, but eventually it was granted. The procession bearing the saintly body was solemnly held on the 11th of June. The fanatical security which these devotions engendered was rudely shattered when, a few days later, the disease burst forth with renewed activity among all classes in all parts of the city. Nevertheless, as Manzoni observes, the faith was such that none recognized that the procession itself was directly the cause of the new outburst of the disease by facilitating the spread of the contagion. Again the belief asserted itself that the ‘untori,’ or poisoners, mixed with the crowd and with their unguents and powders had infected as many as possible. From that day the fury of the contagion continued to grow to such an extent that scarcely a house remained exempt from the disease. The number of patients in the pesthouse rose from 2,000 to 12,000, and later reached 17,000. The daily mortality rose from 500 to 1,200, then 1,500, and is even said to have reached 3,500. Milan, before the epidemic, was said to have had a population of from 200,000 to 250,000. The loss by death has been variously estimated at from 140,000 to 186,000. All these deaths were not due to the plague. Thus, large numbers of children died as a result of starvation consequent upon the death of their parents from the plague.

The horrors attendant upon such a dreadful visitation can well be imagined. Scarcity of help in removing the dead and in taking care of the sick made itself felt, to say nothing of the lack of food. Enormous trenches, one after another, were filled with the bodies of the victims, carried thither by the hardened _monatti_, the counterpart of the Florentine _becchini_, so well portrayed by Lord Lytton in his ‘Rienzi.’ These bearers of the sick and dead were naturally recruited from the lowest criminal classes, and it can, therefore, cause but little wonder that an epidemic of the worst of crimes was associated with that of the plague.

In 1656 Italy was again invaded by the plague, and on that occasion Genoa lost 65,000 of its population by death. About the same time terrible epidemics of the disease ravaged Russia, Turkey and Hungary.

London, in 1665, suffered dreadfully from the plague. The disease appears to have been imported from Holland, where it was known to have existed for some time. The progress of the disease in London has been vividly portrayed by Defoe in the ‘Journal of the Plague Year’ and in the ‘Due Preparations for the Plague.’

It is supposed that the pest had been imported in bales of goods from Smyrna into Holland in 1663. From thence it crossed over to London, where the first deaths were reported about the first of December in 1664. Toward the end of that month another death occurred in the same house, but during the following six weeks no new case developed. About the middle of February, however, a person died of the plague in another house. From that time only occasional cases of plague were reported, although the weekly mortality was rapidly rising and was greatly in excess of the usual rate. Thus, while the ordinary weekly mortality ranged from two hundred and forty to three hundred, this was gradually increased, so that in the third week in January it had risen to four hundred and seventy-four. After a slight remission, the mortality again rose, so that early in May plague cases were reported more frequently. It soon became evident that the plague, as in Milan in 1630, had slowly but surely gained a firm foothold. The increased mortality was undoubtedly due to unsuspected plague cases of either the pneumonic or the septicemic type.

During May, and especially during the hot weather in June, the disease continued to spread. At the same time, the panic-stricken people began to leave the city in large numbers. In July the condition was truly deplorable. To quote Defoe:

“London might well be said to be all in tears; the mourners did
not go about the streets, indeed, for nobody put on black or made
a formal dress of mourning for their nearest friends; but the
voice of mourning was truly heard in the streets. The shrieks of
women and children at the windows and doors of their houses, where
their dearest relations were perhaps dying, or just dead, were
so frequent to be heard as we passed in the streets, that it was
enough to pierce the stoutest heart in the world to hear them.
Tears and lamentations were seen almost in every house, especially
in the first part of the visitation; for toward the latter end
men’s hearts were hardened, and death was so always before their
eyes, that they did not so much concern themselves for the loss of
their friends, expecting that themselves should be summoned the
next hour.”

London at this time had a population of nearly half a million. The deaths from the plague during 1665, as reported in the bills of mortality, are 68,596. By far the larger number of these occurred in August, September and October. The weekly mortality from the disease rose from a few cases in May to over 7,000 per week in September. It may, indeed, be close to the truth when Defoe states that 3,000 were said to have been buried in one night.

The great plague of London in 1665 was by no means the only visitation of that kind. From the time of the black death in 1348, London had a continuous record of plague infection. On an average it had an epidemic of plague every fifteen years. Some of these were fully as severe as that of 1665. Thus, in 1603, with a population of 250,000, there were over 33,000 reported deaths from the plague. In 1625, 41,000 died of pest out of a population of 320,000.

One of the most remarkable facts in connection with the great plague is this--that it was the last in England. The great fire of 1666 is supposed to have extinguished the plague, but this cannot be said to be true. The disease continued to a slight extent in 1666 and isolated cases were reported as late as 1679, but after that date it disappeared completely and from that time until this year England has been absolutely free from the plague. The sudden extinction of the plague in England after it had become domesticated, so to speak, for nearly three centuries, is indeed difficult to explain. Creighton sees an inhibiting influence in the growth of the practice of burial in coffins. But the absence of famine, together with the cessation of domestic wars and strife and the abeyance of want and misery, had not a little effect. As will presently be seen, the extinction of the plague in England was no more remarkable than its disappearance from Western Europe.

The history of plague in the seventeenth century does not close with the London epidemic. From 1675-1684 the disease ravaged Northern Africa, Turkey, and from thence invaded Austria and even reached Southern Germany. The Vienna outbreak of 1679 can be said to have been no less terrible than that of Milan or of London. The deaths from the plague in Vienna in that year have been variously estimated at from 70,000 to double that number.

From Vienna the plague reached Prague, where in 1861 it is said to have caused no less than 83,000 deaths. It is not to be wondered at that a nation scourged by thirty years of relentless warfare, by religious persecution and finally tried thus severely by the plague should inscribe upon the equestrian statue of their patron saint the heart-rending appeal, ‘Lord, grant that we do not perish.’

The close of the seventeenth century saw the disappearance of the plague from Western Europe. In Eastern Europe, however, the disease continued to exist even during the eighteenth century. Nevertheless, a change had taken place for the better, and as the years went on the retrogression of the plague became more and more distinct.

During the first two decades of the eighteenth century the plague was widely distributed in Eastern Europe. It was present especially in Constantinople and in the Danubian provinces. From the latter it extended to Russia (Ukraine), and from thence to Poland. The disastrous invasion of Russia by Charles XII. of Sweden, ending in his defeat at Poltawa in 1709, led to its further dissemination to Silesia, Eastern Prussia, the Baltic provinces and seaports, and even to Scandinavia. It was during this epidemic that Dantzic, in 1709, lost 33,000, and Stockholm 40,000 by the plague. During the years 1709 and 1710 the plague mortality in the Baltic provinces exceeded 300,000. Three years later, in 1713, the plague spread up the Danube and reached Vienna, Prague and even Bavaria.

During these two decades Western Europe was entirely free from the dread disease. In 1720 the disease suddenly developed in Marseilles and extended from thence to neighboring towns and the country districts of Provence. Terrible as was this visitation it is of interest, inasmuch as it was the last occurrence of the plague on French soil, and the last in Western Europe until the recent outbreak in Portugal.

The plague was said to have been imported into Marseilles by a merchant vessel, the ‘Grand Saint Antoine’, from Syria. On its way to Marseilles several deaths occurred on shipboard, but the cause was overlooked. On the 25th of May, 1720, two days after the arrival of the vessel, another death occurred among the crew. The disease was still not believed to be the plague, and although quarantine was instituted, new cases appeared among the crew and the dock laborers employed in unloading the vessel, and it was not until the disease reached the city that its true nature was recognized. The germs of the disease had then been scattered broadcast. Unsanitary a city as Marseilles is to-day, it must have been vastly more so in 1720. The result of the addition of plague germs to the want, misery and filthy condition was at once evident. During August the mortality averaged four and even five hundred per day. In September the daily mortality rose to 1,000. So great was the terror of the populace that it became impossible to secure bearers of the dead, to obtain nurses and attendants. The dead were left in heaps upon the streets, so that it became necessary to transfer to the city 700 galley slaves, who were required to remove the bodies. These same galley slaves were even pressed into service as nurses. The diseased were abandoned by friends and relatives, and under such conditions it need not be wondered at that they received little or no attention from others. Food and water were denied to the unfortunates, and when food was administered to the pesthouses it was thrown into the windows by machinery.

The disease continued in Marseilles until December, 1721, but isolated cases persisted until April, 1722. During the fifteen months of its duration it carried off 40,000 of the population. According to Defoe, there died of the plague in Marseilles and within a league of its walls 60,000.

From Marseilles the plague reached Aix, and in the winter of 1720 and 1721 it carried off 18,000 of its people. It also reached Arles, where, in 1721, out of a population of 23,000, 10,000 died (forty-five per cent). The same year, in Toulon, which had a population of 26,000, the plague attacked 20,000 of the population, and of these 13,000, or about one-half of the original population, died.

The country districts about Marseilles were likewise invaded. Out of a population of 248,000, there died of the plague 88,000, or fully thirty-five per cent.

It is evident from this description that the plague of 1720 was in nowise inferior to that of 1348. Fortunately, the disease did not spread beyond Provence. It is noteworthy that in many instances, in Marseilles, people secluded themselves in their houses, avoiding all communication with the outer world, and in this way escaped. Similar isolation of cloisters, insane asylums, likewise resulted in freedom from the disease which stalked so freely throughout the stricken city. It was experience of this kind in isolation of the healthy which led Defoe to write his ‘Due Preparations for the Plague.’

Toward the middle of the century the plague reasserted itself in the Danubian provinces, the constant battleground between the Turks and Russians and Austrians. In 1738 it not only prevailed in Russia but also invaded Hungary. Of more importance than this occurrence is the outbreak of the plague in 1743 in Sicily. The last epidemic of plague had occurred in Messina in 1624. After a lapse of one hundred and twenty years, it reappeared with terrible results. In Messina, as in Marseilles and in London, the first cases were not recognized as plague cases and, as a result, the infection spread until, like a veritable explosion, the disease developed all over the city. The plague, with its attendant misery of lack of food, and even of water, was in vain combated by religious processions. The plague corpses were in heaps in the streets, as in Marseilles, and cremation was resorted to in order to effect their removal. That year 30,000 died of plague in the city of Messina. With the exception of a slight epidemic at Noja in 1815, this outbreak in Messina in 1743 was the last one to appear in Italy.

In 1755, the plague was introduced into Transylvania by an Armenian merchant from the Black Sea. Before it was extinguished, 4,300 deaths were recorded.

Next to that of Marseilles and of Messina, the most noteworthy outbreak of plague was that which occurred in 1771 in Moscow. The disease was introduced by troops returning from the Danubian provinces. As so often has been the history of plague, the first cases were not recognized, and the existence of pest was denied. When the plague was demonstrated to be present, it is said by Haeser that three-fourths of the populace deserted the city. The disease began early in March and increased during the early summer months. In August over 7,000 deaths resulted, while in September the records show that 21,000 died. In October the plague decreased, but still 17,000 deaths attested to its fearful power. Early in January it became extinct, after a duration of ten months, and after having caused the death of more than 52,000 people.

Toward the close of the eighteenth century, at the time of the Napoleonic invasion of Egypt and Syria, the French armies came into contact with the plague. Bonaparte’s visit to the pest-stricken soldiers at Jaffa has been perpetuated in the historic canvas which is to be seen at Versailles.

During the nineteenth century the plague ravaged Northern Africa on diverse occasions. Constantinople was invaded in 1802, 1803, 1808. It was also present to a slight extent in the Caucasus and in Astrakhan. A notable plague epidemic appeared in Egypt in 1812, and soon spread through Turkey and Southern Russia. Constantinople and Odessa were severely scourged. In Odessa out of a population of 28,000 there died 12,000.

It is a noteworthy fact that the Napoleonic wars, with all their incident hardships and misery, did not develop or spread the plague in Europe. The outbreaks of the disease were limited during this period to Africa and to Turkey, Bosnia, Roumania, Dalmatia and to Southern Russia. Two exceptions, however, are to be noted. In 1812 the Island of Malta was infected and more than 6,000 of its people yielded to the disease. The epidemic of 1815 at Noja, in Apulia, was the first recurrence of the plague on Italian soil since 1743, and thus far it has been the last.

The Balkan Peninsula and Southern Russia were visited from time to time by the plague up to about 1841. For nearly forty years Europe was wholly free from the disease, which, however, continued its existence in Northern Africa, in Mesopotamia and in India. The Russo-Turkish war of 1878 brought the Russian troops into contact with the disease in the Caucasus, and the epidemic at Vetlianka on the lower Volga was unquestionably introduced by such returning soldiers.

Such, then, has been the history of the bubonic plague. No other epidemic disease can be traced authentically as far back as the ‘Black Death.’ The characteristic symptoms, the rapid death, the excessive mortality are all features which have been noted through more than twenty centuries. The plague bacillus discovered in 1894 by Yersin, judged by its effect, is neither more nor less virulent than its early progenitors. It has often died out in a given locality or country, it has even been forced back to its original ancestral home, but still the same type, the same species has perpetuated itself unchanged. If the plague on its present world-wide journey does not cause such terrible outbreaks as it has in the past, it will be not because the germ has been altered by time, but because man has changed in so far as he has slowly learned and profited by the lessons of previous epidemics.

GASOLINE AUTOMOBILES.

BY WILLIAM BAXTER, JR.

To understand the operation of a gasoline vehicle it is necessary to be somewhat familiar with the principle on which gasoline motors act. Briefly stated, it is as follows: The gasoline is converted into a vapor, and in this state is mixed with a sufficient amount of air to cause it to ignite when heated to a proper temperature. This mixture of air and vapor is admitted into a cylinder in which a piston moves freely, this part being substantially the same as in a steam engine. By means of an electric spark or a hot tube, the mixture is ignited, burning so violently as to expand the products of the combustion with such rapidity as virtually to become an explosion. The force of this explosion pushes the piston to the further end of the cylinder, and by means of a connecting rod and a crank this movement imparts a rotary motion to a shaft.

The entire operation is made perfectly clear by the aid of Fig. 1, which is a simple diagram of a single cylinder motor. The chamber _R_ contains the gasoline. Air enters this chamber through tube _b_, as indicated by the arrow, and passes out between the plate _c_ and the surface of the gasoline. The float _d_ keeps the plate _c_ in the proper position regardless of the amount of liquid in the reservoir. The heated gases exhausted from the cylinder pass through the pipe _r_, and thus heat the gasoline so that it vaporizes freely and the air passing under _c_ becomes charged with the necessary proportion of vapor. The mixed air and vapor enter a valve chamber _S_, from which the flow into pipe _e_ is regulated by the movement of handle _a_. In this chamber there is another valve, operated by an independent handle, and by means of this more air can be admitted into the mixture when desired. Through the pipe _e_ and the valve _f_ the vapor enters chamber _Q_, which connects with the top of the cylinder. Suppose the shaft _G_ is rotating, then the piston will be drawn down from the position in which it is shown and thus a vacuum will tend to form in chamber _Q_. This action will cause the valve _f_ to open and the mixture of air and vapor will flow into _Q_ until the piston reaches its lowest position and begins to ascend. At this instant the valve _f_ will close, and then the upward movement of the piston will compress the mixture in the chamber _Q_. When the piston reaches the upper position, after completing the down and up strokes, the lever _l_ and the contact point _p_ will come together, and an electric current developed in the induction coil _M_ will pass through the wires _j_ and _k_ and produce a spark at _i_ between the ends of the metallic terminals passing through the plug of insulating material, which is shown in dark shading. This spark will cause the mixed air and vapor to ignite, producing an explosion that will force the piston down for the second time. On the second upward movement of the piston the gases produced by the combustion of the vapor will be forced out through the valve _h_ into the chamber _T_ and the pipe _r_. The valve _h_ and the lever _l_ are operated by cams mounted on the shaft _m_, and they are so set that the spark at _i_ occurs when the chamber _Q_ is full of the explosive mixture and the piston is at the top of the cylinder. The valve opens when the piston begins to move upward after the explosion has forced it to the bottom position.

As will be seen, the piston must move down to draw in a supply of the explosive mixture; it then moves upward to compress it, and on the second down stroke it is pushed by the force of the explosion. From this action it can be clearly realized that the power developed by the motor comes from the force exerted by explosions at every alternate revolution of the shaft. On that account the cams that move the valve _h_ and the lever _l_ are placed on a separate shaft, which is geared to the main shaft in the ratio of two to one; that is, the wheel _K_ is twice the diameter of the wheel _J_. As the force of the piston acts on the shaft only once in every two revolutions it is necessary to provide a heavy fly wheel _O_, which will store up enough momentum to continue the rotation of the motor through the ineffective revolution. Before the motor can put forth an effort it is necessary for the piston to move downward so as to draw in a supply of explosive gases and then to move up so as to compress them and produce an explosion; therefore, the motor will not start of its own accord, but must be set in motion. In the act of starting the wheel _O_ is turned by hand.

The combustion of the gasoline vapor within the chamber _Q_ and the upper end of the cylinder develops a large amount of heat, and unless means are provided for dissipating it the temperature will soon rise to a point that will interfere with the proper action of the motor. Two ways are employed to carry off the heat. One is by surrounding the cylinder with a water jacket, as shown in the diagram at _NN_; and the other is to provide the exterior of the cylinder with numerous thin ribs so as to increase the surface exposed to the air and thus increase the radiation.

The electric spark is a very effective igniter for the explosive mixture, and, by properly setting cam _n_ the explosion can be made to take place just at the position of the piston that may be found the most desirable; but the points at _i_ are liable to get out of order, and the battery that actuates the induction coil _M_ and the coil itself can become a source of more or less trouble, and on that account the igniting is effected in some motors by means of a hot tube. When this is used the cam _n_, the lever _l_ and the electrical parts of the apparatus are not required. In their stead a tube is placed on the upper side of the chamber _Q_ and this tube is maintained at a red heat by means of a flame impinging against its outer surface. When the explosive mixture is compressed it rises in the interior of the hot tube, and when it reaches the portion that is hot enough to produce combustion an explosion takes place. By many engineers this arrangement is regarded as superior to the electric spark on account of its simplicity.

Gasoline motors are made with one, two or more cylinders, but in each cylinder the action that takes place is that described above. The actual construction of a motor is not so simple as might be assumed from the appearance of Fig. 1; many details are required which are not here shown. A more perfect idea of the actual construction of a gasoline motor can be had from Fig. 2, which is a working drawing of a recent European invention. In this design it will be noticed that the cylinder is cooled by radiation into the surrounding air, the exterior surface being increased by numerous circular ribs and also by extending a hollow trunk from the upper side of the piston, so as not only to increase the radiating surface, but also to allow the hot air to escape from the chamber _T_ in which the crank discs revolve. In this drawing _E_ is the explosion chamber, corresponding to _Q_ in Fig. 1, and the valve _s_ is the counterpart of _f_, while _s’_ corresponds to the valve _h_. The upper pipe _t_ is the pipe _e_ of Fig. 1 and the lower pipe _t’_ is the pipe _r_ of the same figure. Although the crank discs, connecting rods and other details are different in shape, it will readily be seen that their relation to each other is the same.

Since a gasoline motor cannot start of its own accord, it is necessary in vehicles in which they are used so to arrange the driving gear that the motor may be kept in motion all the time and always in the same direction, hence, to reverse the direction of the carriage, reversing mechanism, independent of the motor, must be provided. The most simple mechanism for a gasoline vehicle employing spur gearing exclusively is shown in diagrammatic form in Fig. 3. In this figure _A_ represents the cylinder of the motor, _B_ the crank disc chamber and _M_ the vaporizing receptacle, which is generally called the carburator. The pinion _C_, on the end of the motor shaft, meshes into a gear _D_ which is mounted upon a sleeve _E_ which revolves freely round shaft _G_. This sleeve has its ends formed so as to engage with the gears mounted upon shaft _G_, and by means of a lever, which is not shown, but which works in groove _a_, the clutch either _s_ or _ss_ can be thrown into engagement with its corresponding gear. If _s_ is thrown into gear, as shown in the drawing, the wheel _F_ will turn _H_ and the pinion _I_ will rotate the gear _J_ which is mounted upon the axle of the carriage. If the clutch _ss_ is thrown into engagement, the gear _G_ will turn _K_ and this wheel will turn _l_; but, as can be clearly seen, the direction in which _l_ will revolve will be opposite to its motion when driven through _F_ and _H_, therefore, if when _F_ drives the carriage runs forward, when _G_ drives it will run backward, and when _E_ is moved to the central position, so that neither _s_ nor _ss_ engages with their respective gears, the vehicle will stand still, but the motor will continue to revolve.

This diagrammatic arrangement is more simple than the gearing actually used and is not as complete in action as many of the devices, as it only provides means whereby the direction of rotation of the axle may be changed, while in many carriages the gearing also varies the ratio between the speed of the motor and the driving wheels. It is also quite common to combine in the train of gearing spur gears and sprocket wheels, and in some instances even belts. Fig. 4 illustrates a French gasoline automobile made by Underberg, of Nantes. The first figure is a side view, and the second is a plan of the truck and driving mechanism.

The motor, which is of the single cylinder type, cooled by radiation into the air, is located at _N_. The pinion on the end of the motor shaft engages with the wheel on the end of shaft _A_. This shaft carries four gears, which can be moved by means of lever _C_, so as to engage with corresponding gears on shaft _B_, thus providing four different speeds. The motion of _B_ is transmitted to the rear axle by means of a belt that runs over the pulleys _p_ and _P_, the latter being carried by a differential gear, so as to run the two driving wheels at proper velocities. The circular ribs surrounding the motor cylinder are well shown in the figure, in which the carburator of _C_ is also seen. The housing for the motor is open at the sides so as to give air currents free access. In Fig. 4 the speed changing gears are shown, the reversing train being omitted; but if it were also drawn in, the diagram would be far more elaborate than Fig. 3.

Another form of variable speed gear is shown in Fig. 5. This provides for two speeds. The large wheel _E_ is on the carriage axle, and it is driven either by a pinion _F_, or by _J_. Upon the shaft _O_ there are two friction clutches _C D_, and when _C_ acts the pinion _F_ drives _E_, and when _D_ acts the pinion _G_ drives _H_, which in turn drives _I_, and this wheel is mounted on the same shaft as _J_.

Some of the best-known makers of gasoline vehicles do not employ variable gears and depend for changes in the speed wholly upon variation in the velocity of the motor. The De Dion carriages are made in this way, the gearing being substantially as illustrated in Fig. 3.

Fig. 6 shows a gasoline vehicle made by Panhard & Levassor, who are perhaps the best known French manufacturers of automobiles, as their vehicles have been the winners in all the notable races held within the past few years. The motor they use is shown in Fig. 7, and, as can be readily seen, is of the two-cylinder type, cooled by a water jacket, just as in Fig. 1. The explosion is produced by means of a hot tube, as explained in connection with the last-named figure. This motor is placed under the body of the vehicle, and is connected with the rear axle by means of a train of gearing which terminates in sprocket wheels and chains that connect with driving wheels, each one being operated by a separate chain. In Fig. 6 the sprocket wheel and chain are well defined, and forward of these can be seen the outline of the casing enclosing the gearing.

Fig. 8 shows another European design, in which a variable-speed gear is used. The plan of the truck, showing the general arrangement of the mechanism, is presented in Fig. 9, and the details of the variable-speed gear are shown in Fig. 10. The motor is located at _A_, and through a friction clutch _B_, and the variable speed gear _C_, it rotates the shaft _H_, which runs lengthwise of the vehicle. Motion is imparted to the hind axle by means of bevel gears contained within the casing _D_. The large bevel gear on the axle is of the differential type, so as to drive the wheels _R R_ at the proper velocities.

When a high speed is desired, the variable speed gear, Fig. 10, is set so that shaft _M_ drives _N_ direct, the clutch at _E_ being moved so as to interlock. _N_ is the end of shaft _H_, so that with this connection the bevel pinion, which meshes into the axle gear at _D_, revolves at the same velocity as the motor shaft. By moving the handle _V_, Fig. 9, to the right, an intermediate speed is obtained, and by moving it to the left, the carriage is run at the lowest velocity. When the handle _V_ is turned to the right, the ends _M_ and _N_, which form the clutch _E_, Fig. 10, are separated, and at the same time the lower shaft _H_ is moved toward _M_, so as to cause gear 1 to mesh into gear 2, and also 3 into 7. By this means the end _N_ of the axle-driving shaft is rotated through the train of gears 1, 2, 3 and 7. If the handle _V_ is turned to the left, the shaft _I_ is moved toward _M_, so as to cause gear 1 to mesh into gear 4, and gear 6 into 8, the latter being secured to end _N_ of the axle-driving shaft. The speeds obtained by these changes are in the ratio of nearly 1, 2 and 4.

Fig. 11 shows the plan of a light French carriage, which is equipped with a double cylinder motor, set in a horizontal position above the front axle, and arranged to impart motion to the hind axle by means of belts. The motor, which is located at _A_, turns a vertical shaft, and this, through spur gears, rotates a horizontal fly wheel, _B_. Two pulleys are mounted upon the motor shaft, and from these belts run to tight and loose pulleys on a countershaft, _S_. From the latter the rear axle is driven through two sets of spur gearing, which give two different speeds. By means of the belts, two other speeds are obtained, thus giving, in all, four different velocities. To stop and start, the belts are shifted from the tight to the loose pulleys by a belt-shifter, _f_. At _h_, a muffling chamber is located, into which the motor exhausts, so as to reduce the noise.

The elevation and plan of one of the celebrated French racing-machines, the Vallée car, is shown in Fig. 12. The motor of this machine is of sixteen horse-power capacity, has four cylinders, and is connected so as to impart motion to the hind axle by means of a single wide belt, which is marked _G_ in both the line drawings. The driving-pulley on the motor shaft is located at _H_, and the axle pulley at _H’_. Within the latter there is a train of gears for reversing the direction of rotation of the axle, and also for obtaining the differential velocities of the two driving wheels. There is no mechanism for variable speed, this being obtained wholly by changes in the velocity of the motor. The motor speed can be made to vary through a wide range by using four cylinders, with which it is possible to reduce the velocity so low that it would be likely to bring the machine to a standstill if provided with one, or even two, cylinders. The change in the motor velocity is obtained in part by the action of a governor located in a chamber at _A_, and in part by the action of the electric ignition device which is arranged so that the time when the spark is produced can be varied. The rear axle is so held that it can be moved through a short distance, horizontally, by manipulating the lever _D_, and in this way the belt _G_ can be made tight or loose, thus affording another means for varying the speed. A brake is provided which presses against the inner side of the axle pulley, _H_. This brake is used ordinarily, but in the case of an emergency another brake can be operated which presses against the outside of the wheel in the space between the two sides of the belt. It is claimed for this vehicle that by the elimination of mechanical speed-changing devices, a great deal of weight is saved, and that this is more than enough to compensate for the extra weight of the motor, arising from the use of four cylinders. In most gasoline carriages it is necessary to provide a slow-speed gear for hill-climbing, as the motor cannot put forth a sufficient effort to ascend a steep grade at the normal velocity. With this racing-machine such a gear is not required owing to the enormous power of the motor.