433 



PERUVIC ACID. 



PESTILENCE. 



434 



about 5 or 6 yards high ; it has a regular oval form, of which the 

 greatest axis is nearly 40 feet long. 



In the ruins of the town of Chulcanas, in the department of Truxillo, 

 near the boundary-line between Peru and Ecuador, Humboldt had an 

 opportunity of observing the construction of the private buildings of 

 the Peruvians, and he observes that they consist of one room only, and 

 that probably the door opened into a court-yard. 



Of the ancient Peruvian tombs, the majority are square in plan : 

 have the burial-place in the basement ; a small chamber above, the 

 door to which, at some height from the ground, is the only opening 

 into the tomb ; and flat roofs. Some of the tombs appear to have 

 had domicular roofs ; and remains of a few tombs occur circular in 

 plan. 



(Humboldt, Yues da Cordillires et Monuments des Peuples Indigenes; 

 Rivero e Tschudi, Antiyuedades Peruanca ; Gailhabaud, Monumens 

 Ancletis et Moderns: Fergusson, Handbook of Architecture.) 



PERUVIC ACID. A colourless, inodorous, crystalline acid, formed 

 by acting upon guanine by a mixture of chlorate of potash and hydro- 

 chloric acid. 



PERUVIN. [STTROSE.] 



PESTILENCE is a general term applied to those diseases of an epi- 

 demic character which affect large masses of a population, and are 

 remarkable for their destruction of human life. The two forms of 

 disease to which this term is most frequently applied, are plague and 

 Asiatic cholera. 



Plague is a disease of so fatal and malignant a nature, that to this 

 very circumstance it probably owes its nomenclature. The nosological 

 definition of this disease by Dr. Cullen is perhaps as correct as can be 

 given in few words : " A typhus fever, in the highest degree contagious, 

 and accompanied with extreme debility. On an uncertain day of tbe 

 disease, there is an eruption of buboes or carbuncles." Dr. Patrick 

 Russell, who practised at Aleppo during the plague of 1 760-1-2, informs 

 us that its progress at its commencement is much the same in the 

 several parts of the Levant as hi the cities of Europe. It advances 

 slowly, fluctuating perhaps for two or three weeks ; and although at 

 that period it generally proves fatal, yet it is often unattended by ite 

 characteristic eruptions. Indeed the cases in which the eruption is 

 wanting constitute the most rapidly fatal type of the disease. The 

 general derangement of the system which ushers in an attack of the 

 plague, is much like that which commences the course of ordinary 

 fever. A sense of cold, with some shivering, which is soon followed 

 by heat and acceleration of the pulse, with giddiness, headache, depres- 

 sion of strength and spirits, white tongue, vomiting or diarrhoea, and 

 great oppression about the praecordia, are among the first symptoms of 

 the disease. These are succeeded by a burning pain about the pit of 

 the stomach ; by a peculiar muddiness of the eyes ; by coma, delirium , 

 and other affections of the sensorium, which terminate by death in 

 some cases on the second or third day, before the pathognomic sym- 

 ptoms, buboes and carbuncles, have appeared. In other cases these last 

 mentioned symptoms are present, together with purple spots and 

 ecchymoses, which belong to the plague in common with other 

 malignant fevers. Though these are the ordinary symptoms of plague, 

 they are not invariably observed in the same individual ; but many 

 varieties occur, which chiefly have reference to the greater or less 

 virulence of the disease, and the absence or presence of some particular 

 ins. Thus, we are informed by Sydenham that in the infancy 

 of the great plague of London scarce a day passed but some of those 

 who were seized with it died suddenly in the streets, without having 

 had any previous sickness ; the purple spots, which denote immediate 

 death, coming out all over the body, even when persons were abroad 

 about their business ; whereas after it had continued for some time, it 

 destroyed none, unless a fever and other symptoms had preceded. 

 Dr. Russell describes six classes or varieties of plague, in some of 

 which the fever appears to have been very violent, while in others it 

 was proportionally mild. The most destructive forms of the disease, 

 according to this author, were marked by severe febrile symptoms ; 

 and the infected of this class seldom or never had buboes or carbuncles. 

 The bubo however was the most frequent concomitant afterwards ; 

 carbuncles, on the contrary, were remarked in one-third of the infected 

 only, and were seldom observed at Aleppo earlier than the month of 

 May, near three months after the disease began to spread. The car- 

 buncle increased in the summer, was less common in the autumn, and 

 very rarely was observed in the winter. The absence of bubo and 

 carbuncle at the commencement of the plague has been one of the 

 grounds of contention among writers as to the real nature of the 

 disease. Diemerbroech and some others assure us that no one symptom 

 is pathognomonic of plague, and Dr. Russell concludes that " the plague, 

 under a form of all others the most destructive, exists without its 

 characteristic symptoms, can admit of no doubt." From all the 

 evidence upon this subject that we have been able to collect, it plainly 

 appears that authors are by no means agreed on the existence of the 

 plague as a distinct disease. The symptoms, morbid changes, history, 

 and mode of propagation of plague, bear so close a resemblance to 

 those of the malignant typhus of this country, that it is difficult to 

 regard them otherwise than as types of the same disease. This opinion 

 is strengthened by the authority of Dr. Mackenzie, who resided thirty 

 years at Constantinople. " The annual pestilential fever of that place," 

 , " very much resembles that of our gaols and crowded 



AKTS ASD SCI. MV. VOL, VI. 



hospitals, and is only called plague when attended with buboes and 

 carbuncles." Sir John Pringle too observes, " that though the hospital 

 or gaol fever may differ in species from the true plague, yet it may be 

 accounted of the same genus, as it seems to proceed from a like cause, 

 and is attended with similar symptoms." The buboes which charac- 

 terise plague consist of inflammatory swellings of the glands in the 

 groin and armpits ; the parotid, maxillary, and cervical glands some- 

 times, but less frequently, become affected. These buboes may either 

 suppurate or gradually disperse : when suppuration occurs, it is seldom 

 till the fever has begun to abate, and is manifestly on the decline, as 

 about the eighth or ninth day. Carbuncles consist of inflamed pustules, 

 or angry pimples, which, instead of suppurating, frequently terminate' 

 in mortification. They may be seated on any part of the body. 



The morbid changes that are met with in the bodies of those who 

 die from plague are very similar .to what we find in typhus, yellow fever, 

 and in the carcases of animals that have died in consequence of a putrid 

 matter injected into their veins. The vessels of the brain and its mem- 

 branes are gorged with a dark coloured blood ; the lungs and liver 

 present traces of inflammation or of gangrene ; patches of inflammation 

 and ulceratiou are met with in the stomach and intestines ; the heart is 

 of a pale red colour, easily torn, and full of black blood, which, according 

 to M. Magendie, never coagulates. These changes however are not 

 always found, aud the same absence of appreciable organic lesion is 

 sometimes observed in typhus and other diseases which prove rapidly 

 fatal. No age, sex, or profession appears to enjoy an immunity from 

 plague, nor does one attack secure the individual from future infec- 

 tion ; but it has been observed that old persons, women, and children 

 suffer less frequently and severely from its attacks than robust adults. 

 Some persons also, who exercise particular trades, as knackers, tenners, 

 water-carriers, bakers, and oilmen, seem to share this advantage ; while 

 smiths and cooks were noticed, during the campaign in Egypt, to be 

 more particularly liable to it. One law appears to be universal in all 

 plagues, namely, that the poor are the first aud chief sufferers. In 

 Grand Cairo, Constantinople, and Aleppo, it is in the low, crowded, 

 and filthy parts of those cities, occupied by the poorest people, that the 

 plague commits its greatest ravages. The celebrated plague of Mar- 

 seille, in the year 1720, first appeared in a part of the city noted for 

 the sordid filth, crowded state, and wretchedness of the poor inhabi- 

 tants. This was likewise true of London, where, from the same cir- 

 cumstance, it obtained the appellation of the Poor's Plague. Like 

 many other diseases, plague is observed in two forms : first, as an 

 indigenous and local disease, peculiar to the inhabitants of certain 

 countries, and from which they are never entirely free ; and secondly, 

 as a raging and fatal epidemic, not confined to its original seat, although 

 exhibiting itself there in its most intense forms. It is the epidemic 

 variety of this fatal malady that has engrossed so much attention from 

 the earliest tunes down to the present ; and we shall therefore briefly 

 pass in review some of the principal circumstances which attend its 

 origin, progress, and termination. 



It has been observed that nearly all plagues have been preceded by 

 certain natural signs, and by a greater mortality from malignant 

 diseases generally than at other times. Among these precursory 

 signals, great and sudden atmospheric vicissitudes have been noted. 

 Livy (v. 13) attributes the origin of a pestilence to this cause. " The 

 year was remarkable," he observes, " for a cold and snowy winter, so 

 that the roads were impassable aud the Tiber completely frozen. This 

 deplorable winter, whether it was from the unseasonable state of the 

 air, which suddenly changed to an opposite state, or from some other 

 cause, was succeeded by intense heat, pestilential and destructive to all 

 kinds of animals." But in the great plague of Athens, of which 

 Thucydides has given so minute a description (ii. 48, &c.), he observes 

 that the year of the plague was particularly free from all other 

 diseases ; and he mentions nothing unusual as having occurred in pre- 

 ceding years. The city however was then greatly over-crowded with 

 inhabitants, a great part of the population having taken refuge within 

 the walls of Athens (ii. 16), in consequence of the war. [PERICLES, 

 Bloo. Div.] Russell informs us that the whiter of 1756-7, which pre- 

 ceded the petechial fever of 1758 at Aleppo, and the plague of 1759- 

 60-1-2 in different parts of Syria, was excessively severe. Olive-trees 

 which had withstood the weather for fifty years were killed. In the 

 following summer a dearth ensued from the failure of the crops, and 

 so severe a famine, that parents devoured their own children, and the 

 poor from the mountains offered their wives for sale in the markets to 

 buy food. The connection between famine and pestilence has been 

 noticed in all ages of the world. An enormous increase of insects has 

 frequently been observed to precede a pestilence. We are informed 

 by Short, that in 1612 Constantinople was infested with crowds of 

 grasshoppers of great size that devoured every green thing, and the 

 next year (1613) the plague carried off 200,000 inhabitants of that city. 

 In 1612, swarms of locusts laid waste the vegetable kingdom in 

 Provence; and in 1613 the plague appeared in different parts of 

 France. Locusts and pestilence are frequently mentioned together in 

 the sacred writings ; and we find that the plagues of Egypt exhibited 

 a series of phenomena, rising in progression from corruption of the 

 rivers and fountains, swarms of insects, murrain among cattle, thunder 

 and thick darkness, and a tribe of inferior diseases, to that fatal pesti- 

 lence which swept away the first-born of the Egyptians. In fine, 

 dearth or unwholesome provisions, pestilence amoug cattle, great 



r F 



