ON  DENGUE.
  By this name is known an eruptive fever, or exanthematous affec-
tion, which, in 1827-28, spread extensively over the West Indian
Islands and the neighbouring coast of the American continent.   It
seems to have appeared first in the island of St. Thomas, the  chief
town of  which  it invaded  in September, 1827, attacking in rapid
succession almost every individual in a population of about 12,000.
Towards the end of October, it  passed over to the neighbouring
island of St. Croix.   We  hear of it, in November, in St. Bartho-
lomew's, and in Antigua  in January, 182S.   It prevailed at  Ha-
vanna in the succeeding April, at New Orleans in  May and June ;
and  in July and August affected  very  generally the  inhabitants  of
Charleston, South  Carolina, and reached  Savannah  (Georgia)  in
September and  October.   During the  same  summer,  it is said to
have shown itself at several points on the Gulf of Mexico, south  o(
the Mississippi, and even along the Atlantic coast of South America ;
but we  have no authentic details  of these  occurrences,  which were
merely  noticed in the newspapers of the day. As winter approached,
it ceased gradually, either  having no new subjects to attack, or sub.
siding like other epidemics, and has not, since that period, been met
with any where in  a definite or regularly recognized form ; in this
its brief duration, in the suddenness of its appearance,  in  the rapi-
dity of its spread, and in its total subsequent extinction, offering a
striking resemblance to the Black Death* of the fourteenth century,
and  the Sweating Sickness of the sixteenth, and several other shapes
of pestilence which have at different points of time arisen and died
away, scattering among the nations horror and affright.   Happily,
however, as the record will show, it was much unlike these plagues
in proportional mortality  ;  bringing in its train infinitely less of
danger  and of death than of mere suffering.

   *  Heckers History of the Black Death was republished in the Select Medical
 Library  for 1836-7.—tin. Lib. 
6
DICKSON ON DENGUE.
  No definite signification is attached to the title by which it came
to be universally known.  The negroes at St. Thomas called it " the
dandy fever," from the  stiff, affected gait of those  labouring under
it.  In Cuba it was termed " Dengue or Dunga ;" whether  this is
merely a modification of the English slang-word dandy, thus altered
in Spanish pronunciation, is not clear.  One writer affirms that the
word occurs in the vulgar cant of the lower classes in Havanna,and
is used to denote  the  staggering uncertain  walk of an intoxicated
man.   We shall see, as we proceed in the description of the disease,
the application of these phrases.
  Symptoms.—Dengue usually  made its attack with pain, stiffness,
and swelling of some of the smaller joints, often of the muscles of a
limb, rigidity  of "the  neck, aching of the back and  loins.   These
pains were followed, after an uncertain though generally brief period,
by headache—suffusion of the eyes—abrupt, full, frequent pulse—hot,
pungent, dry skin—restlessness, thirst, and  other tokens  of  febrile
excitement.  The fever did not  remit, but declined and disappeared
in a great majority of cases on  the second or third day.   In this
early stage the tongue was generally clean, and the stomach quiet,
but sometimes there was nausea or even vomiting.  The determina-
tion to  the  head  was  occasionally violent.  Instances occurred in
which delirium was among the first symptoms, coming  on at the
commencement,  and  enduring until the subsidence of the  febrile
paroxysm.  At this time  the skin  lost its heat and dryness, be-
coming relaxed, with abundant perspiration ; and the local pains were
all lessened in degree.  A sort of miliary eruption or rash in some
persons attended this sweating stage, and in a few others preceded
 both the local pains and the fever.  It was, however, as  connected
 with this first stage of dengue, a very inconstant affection, seeming
 rather a merely accidental coincident than a symptom.  The  pains
 of the joints and muscles  which, as has been said, were diminished
 in severity at the subsidence of  the febrile  exacerbation, did not
 go off entirely :  a degree of swelling, stiffness, and  tenderness  of
 the affected parts  remaining  permanently, though  varying much
 in  intensity  in different individuals.  This condition of things con-
 stituted a sort of deceptive  interval  between  what  may  be de-
 scribed as the first and second stages of this strange disease.  Many
 now believed themselves to  have past  through  the attack, and
 attempted to  resume their ordinary occupations ; but soon had occa-
 sion to discover  that their sufferings were  by no  means at  an end. 
DICKSON ON DENGUE.
7
On the third or fourth day, there being no fever present, or a very
obscure degree of it, the tongue would  begin to be coated with a
yellowish fur, and the  stomach would become  distressed, uneasy,
and irritable.  The patient was now low-spirited, fretful, and anx-
ious.   Vomiting  came  on in  some, with great languor, lassitude,
and  debility, and restlessness  at  night.   This was regarded  as  the
most oppressive  and  insufferable  of the  stages  of the malady.
On the fifth or sixth day from  the invasion, the  period varying
somewhat  in  different individuals,  the  annoying  symptoms just
described were relieved by the coming out of an abundant eruption,
met with  so constantly and  in  so very great a proportion of the
cases, that it clearly demands  to be considered a characteristic and
essential circumstance in the history of the disease.   It consisted of
minute papulae, somewhat elevated, of a florid  red, and distributed
in irregularly-shaped patches  ; the feet and hands being somewhat
swollen, with a sense of numbness and thickening.   It appeared  first
on the face, then on the trunk  and thighs, gradually spreading to the
extremities.  It resembled scarlatina more than measles in the hue
and aspect of the skin, but was less diffused or confluent than either.
When fully developed, it was attended with some itching and burn-
 ing of the surface, and at this time a second febrile paroxysm came
 on with return or aggravation of the muscular and arthritic pains.
 Inflammation and enlargement of the lymphatic glands in the neck,
 axilla, and  groin attended in  a good many cases ;  these parts being
 apt to  continue swollen  and  painful for some time after convales-
 cence was fairly established.*  The eruption disappeared after two
 or three days' duration, becoming gradually paler, with some des-
 quamation of the cuticle.
    Of all the symptoms of dengue the affection of the joints was the
 most  tenacious  and  troublesome, adhering  for  weeks to  some
 patients, and  constituting a sort of permanent lameness or loss of
 mobility.   Nay, even now (January, 1S35), some of the population
 of cities visited by this plague persist in speaking of the rheumatic
 or quasi rheumatic decrepitude and pain under which they labour
 as " the effects of the dengue."
    All classes of persons were subject to this singular exanthem, and
 all equally and alike.  The aged and the young, the infirm and the
 robust, the native  and the stranger, the black and the white, all
* In a few instances, suppuration of these tumours took place. 
8
DICKSON ON DENGUE.
shared the  same sufferings.   Very young children were liable to
the disease, even from a few days after birth ;  nay, some were sup-
posed to be actually born with it.  The circumstances of these latter
cases are described as follows :—The mother having recently passed
through the attack, or still labouring under it, the skin of the infant
at delivery was observed to  be of a scarlet red, the tongue and lips
smooth and fiery ; it was obviously in pain, and could not bear to
be  disturbed,  screaming violently  if lifted,  or if its  limbs were
moved ever so gently.   Below the  fifth year of age,  convulsions
very often  attended  the  invasion, and in  some  instances  were re-
peated with frequency throughout the whole course  of the  attack.
In very advanced life, there was, from the first, great debility and
extreme prostration.  Some  old people were afflicted with erysi-
pelatous inflammation of the lower extremities, supervening after the
eruption had disappeared.
   Pregnant women when attacked were very liable to abortion, and
a remarkable number of miscarriages and premature labours occurred.
The violent pains in the back and  loins, which came on  so generally
at  the  invasion, extended   downward into  the  thighs,  and the
uterus  being  thus  excited,  the  foetus  was  ultimately expelled.
A sore  mouth  was among the frequent symptoms of  dengue, and
one or  two instances of  pretty severe glossitis occurred.   In the
worst  of these, the appearance of  the organ has been  completely
altered, and its functions much impaired, indeed nearly abolished ;
the articulation being extremely indistinct, and the capacity of ap-
preciating  taste  and flavours singularly defective.   The surface  of
the member is intersected with deep lines, which divide it in every
direction, like  flesh  which has been  "chopped"  for culinary pur-
poses.  The ulcers  formed  in the  mouth were often very irritable
and painful, and healed slowly and with difficulty.   Then followed
a free flow of  offensive saliva, with lividness  and sponginess of the
gums, offering considerable  resemblance to  the symptoms of  mer-
curial  ptyalism.  In a  few cases hemorrhage occurred from the
gums and fauces.
   Pathology.—Dengue  is to he classed  properly among  the ex-
anthemata.   It is an eruptive fever of distinct and specific character.
Its essential symptoms are, in the first  stage, a painful affection of
the joints  and muscles ;  and in the second, divided  by an interval
obvious and sufficiently regular, a cutaneous eruption.  The arthritic
inflammation of the first stage was attended by fever of the ordinary 
DICKSON ON DENGUE.
9
inflammatory type  of twenty-four  to  forty-eight  hours' duration.
The eruption was preceded, as is usual in the exanthemata, by con-
siderable gastric oppression, with nausea  and sometimes vomiting.
Let us separate the characteristic from the incidental circumstances
of its history, and from the  former proceed to designate  its correct
name and true pathology.  1. An  arthritis—a painful and apparently
inflammatory affection of the  joints—was in a vast majority  of in-
stances its earliest symptom.  The attack was rarely ushered in by
a formed chill or febrile rigour.   In general, the very first indica-
tion of  seizure consisted merely  in  a painful affection of some
joint or limb.   In  the case of  the  writer of this article, a  single
finger of the right  hand became swollen and stiff for more than  an
hour before any other symptom  of  the invasion  was observed.
Other joints then became successively  painful, and after a consider-
able interval, fever supervened, ushered in by headache, &c.  A
child, four years old, complained, on rising early in the morning, of
pain in the  foot ; his hand  next became stiff, then his knees, &c.,
but he ate his breakfast  as heartily as  usual—the  disease gradually
developing  itself during a space of at least five hours before any
febrile exacerbation could be perceived  ; though the pulse, breathing,
and condition of the surface were frequently examined.  A very old
negro woman was ascending a stair, when she was suddenly seized
with such severe pain,thatshe was utterly unable to proceed.  Her fin-
gers, the chief seat of her complaints, were all of them bent, and could
not be straitened, and the intensity of suffering was such that she lay
prostrate with  tears, and loud  cries, and sobs.   Some hours elapsed
before she had any  fever, and then there  was but a moderate
paroxysm.  In a very stout and manly youth, the pain at the very tips
of the fingers was so intolerably severe that he wept bitterly.  He
had been  much relieved  by  fomentations and opiates  before any
degree of fever supervened.
   As it  was the almost universal fact that these arthritic affections
had thus endured for some time before the invasion of fever, with its
ordinary concomitants,  headache,  red eyes—full, abrupt, frequent
pulse—hot, pungent, dry skin, thirst, &c, so it was rather uncommon
to find the stomach notably disturbed at this period or stage. Among
the other irregular or incidental symptoms, was an eruption already
mentioned, which  showed itself occasionally thus early.   It was a
mere rash,  and was met with  oftener in children than in adults.
   2. The characteristic eruption made its appearance later, after the 
10
DICKSON ON DENGUE.
subsidence of the febrile paroxysm, and constituted a distinct second
stage.  After a duration, varying in different cases, the pain and in-
flammatory  fever above described abated, or went off to the great
relief of patients, who often thought themselves now quite well, and
whose sufferings indeed sometimes, though in a very small minority
of examples, ended here.  But it should be remembered, that when
the  case was thus abruptly terminated without a second stage, the
patient was liable to be attacked again and again  with the  arthritic
affections and otheir rilments of the first stage.
  The eruption  which  has  thus  been indicated  as  essential, was
preceded by great gastric  distress, which, as in  all the other exan-
themata, diminished as the skin became suffused, and was followed
by a sort of secondary febrile exacerbation.  It should be remarked,
too, that the arthritis, which had been greatly relieved, returned at
this time, henceforward remaining pertinaciously annoying for an
indefinite period.
  This singular union of an eruptive fever with inflammatory affec-
tion of the joints, deserves surely to be regarded as  a new and pe-
culiar malady—a form of disease hitherto unknown and undescribed.
The West Indian practitioners, who first met with it, did not fail to
notice  this  combination of  circumstances which  formed  the pro-
minent points in its history, and indeed gave it character.  Hence one
styles it scarlatina rheumatica.*   Another exanthesis arthrosia,\
and a third designates it " an eruptive articular" or rheumatic fever.J
But the vulgar appellations  given it by  the English negroes at St.
Thomas, and by the common people of  Cuba, have prevailed, and
are in general use.
  As it extended  itself  in various directions,  some  of  its more
striking features may have been softened down, or it may have been
impressed with certain modifications by the influences  of  locality,
or  by mingling with endemic diseases.  In this way, perhaps, we
may best account for the fact, that some  of the physicians who met
with it in the latter months  of its brief existence, have suggested
its  resemblance to or identity with other and well known  forms of
fever.   Thus Osgood and Lehman, who saw it  in Cuba, seem dis-
posed to regard it as  the ordinary fever of that region, under certain
peculiarities of circumstances not  well explained ; and Waring of
Savannah dwells upon its close analogy with the " breakbone fever

  * Cocke, Edin. Journal.        f Nicholson, ib.        % Stedman, ib. 
DICKSON ON DENGUE.
11
of 1826, and the epidemic fever  of  1827" (a bilious remittent), in
that city. Still closer are the points of similarity which may be found
in the history of the  breakbone fever or remittent  described  by
Rush* as prevailing in Philadelphia  in the summer and autumn of
1780, and the epidemic  of Calcutta and Berhampore portrayed  by
Dr. Mellis in 1824-25.
   Rush's Fever was met with in July.  It affected all ages and both
sexes.   Medical men would  seem to have been specially liable to it.
No other  febrile disease was observed during its  prevalence.  It
came on sometimes with rigour, seldom with a chilly fit, and often
without any sensation of cold.  Many instances occurred in which
it was introduced by a delirium.   The pains which accompanied it
were excessively severe in the head, back, and limbs ;  in some they
affected the neck and arms, and in one case produced  a difficulty of
moving the fingers of the right hand.  Hence the disease was some-
times believed to be a rheumatism, but its more general name among
all classes of people was the  " breakbone fever."  A nausea univer-
sally, and in  certain instances vomiting  attended.   A  screatus or
constant spitting was  in  many cases observed through the  whole
disease.  The bowels were in most cases regular.  The tongue was
generally moist, and of  a yellow hue.  The skin was moist, espe-
cially when the case terminated on the third or  fourth day.  The
pulse was quick and full, but  never hard ; there was little or no thirst.
A rash  often appeared on the third or fourth day, which proved fa-
vourable ; it was  accompanied by  a  burning  in the palms of the
hands and soles of the feet.   At this time, many people who were
not confined  to  bed, and some who had  no fever, had an efflores-
cence on their  skins.  Convalescence was slow and tedious.  A
bitter taste in the mouth and a yellow tongue continued for nearly a
week.  Most of those who recovered complained of nausea and total
want of appetite.  Great dejection of spirits was the most remarkable
attendant on convalescence.  A young lady proposed, he  says, to
change the  name  of  the disease, and to call  it in that stage  the
break-heart instead of the breakbone  fever.  A remark to the same
purport, and almost in the same words, was made to the writer by a
Spanish woman recovering from dengue, who  had never heard of
Rush or his writings.  The mildness of the requisite treatment, and
the small proportional mortality, are, also, points  of resemblance.
•  Vol. i. p. 216. 
12
DICKSON ON DENGUE.
The differences, however, are not less marked and  striking.   In
Rush's Fever there were remissions every morning, and sometimes
in the evening.  The exacerbations were more severe every second
day, and sometimes two exacerbations occurred in one day.  When
the fever did not terminate on the third or fourth day, it  often ran
on to the eleventh, fourteenth, and even  twentieth days, assuming
in its progress typhoid symptoms.   Rush does not regard  the erup-
tion as an essential or  even a very prominent part of the disease.
Indeed, he does not describe it at all, merely  terming it " a rash ;"
though he speaks of  it as a frequent and favourable symptom.  On
the whole, it seems reasonable to conclude, that the  two  maladies,
although presenting some curious coincidences, are in nature essen-
tially distinct and different.   One  being an eruptive fever, new,
specific, and peculiar,—while the  other  is nothing  more than an
autumnal remittent, a mal'aria fever, somewhat modified by an un-
known agency.  And the same remark applies with  equal correct-
ness, but with more force, to  the epidemics referred to by Dr. War-
ing of Savannah, who makes  his breakbone fever  of  1826 identical
with  the  autumnal fever  of  1827, which again  he looks upon as
identical with yellow fever ; thus mingling in promiscuous confusion
yellow  fever,  ordinary bilious remittent,  breakbone fever,  and
dengue.   Dr. Daniel of the same city considers "  dengue  to be cer-
tainly an exanthematic fever," though he does not regard its inva-
sion in  1828 as its first occurrence,  but believes  it to have existed
previously in 1826, when it bore the name of the breakbone fever.
He contends justly for the essential nature of the  eruption, and re-
marks forcibly upon the danger of treating it  as an accidental symp-
tom.   He states, that when it has been repelled or prevented from
appearing by mismanagement, almost every  part of the  system is
liable to be attacked.   Several cases of mania, consequent upon re-
pelled eruption, he affirms,  occurred within his  observation, and
refers to a case  of tetanus thus produced, which  terminated fatally.
   Dr. Osgood of Havanna has suggested that the cause, origin, and the
nature of dengue are identical with those of yellow fever.   It would
seem scarcely necessary to do more than compare the descriptions
of the two to be struck with  a strong impression of their utter dis-
similarity  ; the following  discrepancies, however, may  be  briefly
alluded to, as clearly disproving any relation  between forms of dis-
ease  so  distinct.  In the  city of  Charleston, S.  C, where yellow
.fever  is  frequently met   with, it  prevails   only  in the autumnal 
DICKSON ON DENGUE.
13
months, August, September, and October ;  very few cases having
even been known to occur in July.   It is the disease of unacclimated
constitutions—emphatically " the  stranger's fever."   Native chil-
dren are occasionally attacked by it ; adult natives and  old residents
may be said to  be secure from its invasion ;  a rule to which the
exceptions  are  as  infrequent as  second attacks of small-pox  or
measles. African negroes are not susceptible of it.  It never extends
into the surrounding country, and notoriously respects such portions
of  the  suburbs  as are particularly  elevated, dry, and airy.  But
dengue made its entrance  into Charleston in June, and  spent its
force before the end  of July ; it attacked promiscuously  native
adults, the oldest residents, strangers, children, and negroes, whether
natives or Africans.   It allowed  no exemption to any locality of
suburban  residence, and spread, though to no great extent, in the
neighbouring country.
   It is still doubtful where dengue originated or first showed itself.
Allusion has been already  made to an epidemic which prevailed in
Calcutta and its environs in 1S24-25.  From the description of that
pestilence, in a  paper published in the Transactions of the Medical
and Physical Society by  Dr.  Mellis, it would  really seem to be
identical  with the dengue  of the West Indies  and Charleston.   Its
universal sway," attacking alike the new-born infant, the aged, the
robust and  the  weak,  the rich and the poor—the suddenness of its
invasion—intensity of pain in the muscles and joints—the heat and
scarlet red  colour of the skin—the eruption or  rash being succeeded
by exfoliation of  cuticle—these are phenomena common  to both.
The sequelae are equally  analogous."  Dr. Mellis notices " great
 prostration  of  strength  and  general  debility,  weakness of the
 stomach, continued  pains in the joints and  cedematous swellings  of
 the extremities."    Such are the familiar effects of the dengue.
    It is proper, next, to inquire  into the  cause or source of this
 exanthem.   Nothing  has  been distinctly indicated on this point in
 the history of the Calcutta and Berhampore epidemic, assuming this
 to have been the dengue.   Of the  West Indian Islands, St. Thomas
 was first attacked.  This  is considered one of the most unhealthy
 situations among them ; the town being a free port, rich and popu-
 lous, and possessing an excellent  harbour, is always crowded with
 vessels from every part of the world.   St. Croix, described as the
 very reverse of St. Thomas  in its physical and political character,
 and universally reckoned one of the  healthiest islands,  was  next 
14
DICKSON ON DENGUE.
assailed.  " So high," says Stedman, " is its reputation for salubrity,
that it has of late years  become a favourite resort for invalids from
the United States of America, where it is considered the Montpelier
of the West Indies."
   The  writers on this  singular disease may be divided into two
classes, one of whom confounding  it with other mal'aria  fevers, re-
gard all investigation into any special or particular cause of its pro-
duction as superfluous ;  while their antagonists, considering it as of
novel and specific character, conceive  it necessary to follow up  the
inquiry, and trace it  to  its peculiar source  or origin.  From what
has been said above of its history and  characteristic phenomena, it
will be readily inferred  that the author of this article belongs to the
latter class of physicians, and believes it to  be capable of  proof, that
dengue is a malady of contagious nature.  We hear of it in Bengal
in 1S25.  After  the  silent progress  of a  year and more, it shows
itself in 1827 in a free port, in the Caribbean Sea, where  ships from
every quarter of the world find ready entrance.   Stedman says, it
was alleged to have been brought  there  by a  vessel  from Africa.
He  thence  traces  it  satisfactorily to St. Croix.    Successively
affecting  the remaining islands, it  reaches Cuba  in the spring of
1828, whence, in June, it obtains  easy access  to  Charleston, New
Orleans, Vera Cruz, and Carthagena.   In each  of  these  cities  it is
attributed to  contagion as an  obvious source,  and  is regarded as
having been imported from some point at which it was known pre-
viously to exist.
   It  is, however, a matter of acknowledged difficulty to prove to
absolute demonstration, the  contagiousness of any form of disease
which is  not capable of being communicated by inoculation.*  In
the instance of such maladies, an attentive observation of  all the
circumstances  of their  origin,  history, and progress  offers us the
only  means of arriving at a probable conclusion  concerning their

   * This is the  experimentum cruris, which, when it can be applied, puts the
question fairly to rest.   In cases which do not admit of  it, the discussion seems
likely to be interminable.  The contagious nature of several shapes of pestilence,
of plague, of typhus, and even of rubeola and pertussis, has been and still is
denied by certain medical sceptics.  The majority of physicians are, neverthe-
less, disposed to admit that, in these and perhaps other analogous instances, an
impalpable virus is generated, which, when thus  eliminated, is diffused at once
through the atmosphere and becomes only cognizable by its effects in the repro-
duction of similar disease to that  from which it emanated. 
DICKSON ON DENGUE.
15
nature and properties.   Rational probability, indeed, is the utmost
that we can here attain, and an ingenious caviller may always suc-
ceed in  throwing in our way objections and difficulties which shall
oppose themselves to any positive decision of the point in dispute.
Two special objections are offered by those who deny the contagious-
ness of  dengue, and  the same have been, with equal correctness,
applied to  the cases  of measles,  scarlatina, and hooping  cough.
The first is the fact that, when you  have traced such disease as far
back as you can, you still must arrive at a spontaneous origin, or its
production from  local and obvious  causes, and they  perceive, or
affect to feel, no more hesitation in supposing several spontaneous
sources than one.  They also assume the principle,  that no disease
which has been generated in any other mode, or by the operation of
other influences, can  take on  in its  progress a  contagion, and be-
come capable of spreading itself in this way.
   But even small-pox must have had a  beginning, and syphilis and
psora, both of  which  may be produced by uncleanliness of person,
are capable of communication to the cleanly.  Still farther, although
we are  here entering upon debateable ground, it is  not always  pos-
sible to trace continuously from step to step the course of measles,
or hooping cough,  or scarlet fever.  They seem  occasionally to
arise in positions insulated from all  chance of contagious transmis-
sion by any mode.  Few  physicians at the present day doubt the
contagiousness of typhus—a  doctrine to the  support of which as
large and weighty a mass of testimony could be adduced as to  any
other in medical science.  But it  is well understood that typhus is
often generated under certain concurrent circumstances, with which
the profession  is familiar, and that  one case so generated may be-
come a centre  from  which the disease shall diffuse itself on all sides.
The  second objection  alluded to is the rapid spread  of  dengue
whenever it has appeared.  The circumstance forms a striking fea-
ture in its character.  But there is nothing peculiar in this part of
its history, and it is most illogical  and  unscientific to  regard the
epidemic prevalence of disease as disproving its contagious power.
The phrases epidemic, epidemic constitution of the  air, and the  like,
which are in common use among practitioners  of  physic, have no
definite meaning ; they refer exclusively to the general extension
of disease.  But no  one, at all conversant with the history of dis-
ease, can  entertain a doubt of the tendency of all febrile maladies,
whether  contagious or not, to become epidemic ; that is, to spread 
16
DICKSON ON DENGUE.
themselves  in this  prompt, universal,  and  irresistible  manner.
Small-pox, measles, hooping-cough—all afford frequent illustrations
of this principle.   It would be ridiculous to pretend to trace all the
cases of these that occur, when they prevail in any population, from
one to another, and thus to account for every individual instance of
its supervention.   As in dengue so in small-pox, persons are attacked
who have been altogether secluded, whether accidentally or through
caution.
  In all discussions of this kind, the first step to be taken is to de-
cide upon the relative value of negative and affirmative statements—
the  proper rule being that which Haller has laid down in philosophis-
ing upon physiological experiments and inferences,' that negative ob-
servations are  entitled to little or no weight, when in opposition to
positive  assertions.'   If, for  example, a very few instances were
brought forward upon good testimony of the spread of any infection
in certain specified communities, additional numbers would be of no
farther importance than this,  that they should, by diversity of posi-
tion and circumstance, obviate the suspicion of a  local cause com-
mon to  all affected.  Suppose it  to be made out, that a given  malady
being introduced into  five such  communities, had  spread itself
among them, seizing a few, many, or  all within its sphere, it would
be  to no purpose to reply to  the inference of its contagiousness
drawn from such statement, that in  twenty, fifty, or one hundred
other instances of similar introduction, it had failed to occasion any
such extension, or give rise to new cases.
  Contagion, perhaps, of all the morbid agents which produce dis-
ease in  the animal constitution,  would seem, on first consideration,
the weakest—inasmuch as it  requires the greatest number and vari-
ety of concurrent circumstances to favour or ensure its impression;
while on the other hand, that which  we term, after Sydenham, the
epidemic constitution  of the air is vastly the  most pervading and
powerful.   Every physician fails   occasionally  in  transmitting
vaccine and small-pox by inoculation.  But when the latter becomes
epidemic,  it is known to  affect persons  most perfectly  secluded,
and guarded with all possible nicety against every  imaginable ap-
proach of diseased subjects and  every shape of fomites.  What  is
the epidemic condition of the air in this latter case, but the solution
or diffusion within it of the  matter of contagion ?  What  is it in
any case but the diffusion throughout  the atmosphere of the  cause of
disease, whether  contagion, or mal'aria, or some other unknown and
undefined agent ? 
DICKSON ON DENGUE.
17
  Not only is the impression of contagion thus uncertain, as is proved
by its failure, but its sphere of action  is contracted within narrow
limits—a  few feet probably, as most writers agree.   Whether this
is the mere result of dilution, or whether the eliminated virus under-
goes some alteration  in its specific properties, in consequence of its
admixture with air, is not determined.   When we take into consi-
deration these circumstances, and reflect farther upon the ordinary
healthfulness of communities among whom contagious diseases are
suddenly intruded, and the general  absence or negation of that pre-
disposition upon which disease  requires so  uniformly to be built up,
we shall rather wonder that contagious maladies spread themselves
so often and so far as they do, than that they should be confined
usually within certain observable limits as to  the extent of trans-
mission and number of subjects, and that they should so frequently
be suddenly lost, and seem to terminate abruptly, as in the case be-
fore  us, a short though very remarkable existence.
   It is for the most  part  a difficult task to  point out the precise
origin of any form of disease, and with respect to what are called,
vaguely, general epidemics, the attempt has been notoriously futile.
Local epidemics, however, among which dengue must of course be
ranked, if its contagious nature be denied, are always, as pneu-
monia typhoides, for example, limited to particular season and tem-
perature ; or, as  in  the case of bilious  remittent,  dysentery, and
yellow fever, to certain localities and circumstances of soil and sur-
face  conjointly with  season and temperature.  But  dengue has, in
its brief career and  well  known  history, shown no correspondence
with any of  these, being  neither limited by season, local position,
nor  atmospheric change.   Its gradual  progression  from  one  place
to another, allowing  abundant room for the anticipation of its arrival,
and the fact that " it followed," from the time when  it first appeared
upon the  American coast, " the great routes of commercial inter-
course," are strong  evidence in favour of  its  contagiousness.   But
there are positive and  marked facts which  seem to us to leave no
room for reasonable  doubt on the subject.
   Dr. Stedman traces the communication  of dengue clearly from
St. Thomas to St. Croix.   Clmstianstcedt,  which  is the seat of go-
vernment of the latter, and on this account, and from its  proximity
to the former island, enjoys a freer intercourse with it, was invaded
a week or two before the town in which he resided, Frederickstoedt.
The first patient whom he saw  had  arrived three days before from
                              2* 
18
DICKSON ON DENGUE.
St. Thomas, and the disease appeared first in the family with whom
this patient had come to reside ; among them, indeed, it raged ex-
clusively for some time, with the exception of a family residing
opposite, the head of which  had frequent mercantile  business with
Christianstcedt.  From there it extended through the town.  " The
disease," he says, explicitly, "spread from family to family, and
from estate to estate, exactly in proportion to their contiguity,  or to
the intercourse that might happen to exist ;" and gives an instance
of the latter kind, when, from  the  communication  between  two
estates belonging to the same master, the one near town and the
other four or five miles distant, the negroes on the latter estate  " got
the disease at a time when it had not spread to any  other in  that
neighbourhood."
  In  the city of Charleston, the earliest cases  happened in  per-
sons connected  with vessels that had arrived from   the Island of
Cuba where dengue then prevailed.   This  fact  is  clearly made
out upon the authority  of two physicians of the highest respecta-
bility.  Professor  T. Prioleau attended the first patient, a negro,
who was put on  board the brig Emmeline just in port, whose cap-
tain had  been ill with dengue a few days before he left Havanna.
The next persons attacked were the ship-carpenter and his family,
who went on board to effect some repairs in the same vessel.  From
these the disease spread as from a centre.  A short time after  these
events occurred, Dr. P. G. Prioleau was called to attend the family
of the captain  of another vessel, who had arrived here about the
same period, labouring under the  disease. The dates in these in-
stances are worth recording.  Captain W. arrived in  Charleston on
the 31st  of  May, ill of dengue ; on the 20th of June,  his wife was
seized ;  on  the  1st of  July,  two of his daughters ;  on the 2d, his
son ;  " it soon extended to the rest of the family."   Prof. Prioleau's
fyst case, the negro above mentioned, was taken ill on the 10th of
June ; his second case  on the 23d.   Here we have two central spots
whence the dengue rapidly diffused itself throughout the city.  These
early patients were  far  from being  in the same neighbourhood.
The brig Emmeline lay at Knox and Pritchard's wharf, in the  upper
part of the town.  Capt. W. resided  in Tradd-street, nearly or quite
a mile distant.
   Farther circumstances of a similar nature deserve notice, as tend-
ing to throw some light  on  the  nature  and h'story of this strange
affection.  It made its  appearance  at  two points in the vicinity of
the citv, the qualities of the soil and  atmosphere of which were as 
DICK80N ON DENGUE.
19
strongly contrasted as possible.  One of  them, Haddrit's  point, is
an elevated sandy bluff, about four miles from Charleston, across the
bay, noted for the salubrity of its air, and the health of its inhabit-
ants.   It has never been invaded by the  yellow fever, even in the
most  pestilential  seasons of  its epidemic prevalence.   Yet some
cases of dengue occurred there, introduced, as he himself has stated,
by  a clergyman whose family  resided at  Haddrit's, while he  at-
tended to his official duties in the city, and by " a neighbour similarly
situated."  The second instance was that of a plantation lying about
four miles from  Charleston,  in the opposite direction, in a low
mal'aria country, the residents upon which were annually subject to
ordinary remittent fevers.   The head of the family and  a  negro
having visited the city, were both taken ill  in about a  week after-
ward ; the wife  of the  former was next seized, and  the disease
afterwards extended among both the whites and the negroes in the
place.
   Prognosis.—The prognosis, in  this  singular affection, was  re-
markably  favourable.   Perhaps no form  of disease is known in
which the proportion of deaths is so small compared with the num-
bers attacked.  Influenza alone  spreads with a universality of inva-
sion at all resembling it, and even influenza is inferior in the infre-
quency of exceptions to its attack.  " In a population of about 12,000
souls who occupy the town of St. Thomas," says Stedman, " scarcely
a single individual escaped."  In all  its seats, few died ; whether ma-
naged by the best professional  skill or mere domestic attention, or
totally neglected.  Yet there was a  vast difference in the degrees of
this suffering undergone by different patients, and not a little in  the
duration of this suffering, and in the rapidity and perfectness of their
convalescence.  The aged  were most severely handled, remaining
frequently  infirm  and debilitated,  with languor and  emaciation.
Corpulent persons usually suffered much, and recovered very slowly.
The intemperate paid  in this, as in every other form of disease,  a
heavy tax for their degrading indulgences.  In  many  it served to
usher in formidable paroxysms of delirium tremens.   Dengue, in-
deed, can hardly be said to have ever proved fatal of  itself.  The
rare instances in which patients died, while labouring under it, pre-
sented some  complication  under  whose incidental  symptoms  the
patient sank ; or some extreme feebleness of constitution in which
the remedies employed were  productive of fatal effects.   More than
one example of this nature is placed on record. 
20                   DICKSON ON DENGUE.

   Treatment.—The violence of the early symptoms of this singu-
lar malady seemed to call imperatively for the most prompt and im-
pressive measures.  The lancet was the favourite resort of a majority
of practitioners, who ascribe to it a notable power in controlling the
force of the attack, and lessening the duration of the patient's suffer-
ings.   Cathartics and diaphoretics were also almost universally em-
ployed—each physician  selecting those formulae in which he had
most confidence.  Both the saline and mercurial purgatives had their
advocates, and were maintained to be specially adapted to the case.
The antimonials, in  the earlier stages, and afterwards Dover's
powder, and the other stimulating diaphoretics, were in general use.
The ordinary domestic practice, and a large majority of cases were
treated without professional aid, consisted in the administration of a
mild purgative  combined with or followed by  a sudorific,  as the
solution of epsom salts in infusion of seneka, or  serpentaria, or hot
lemonade, until the bowels were freely opened ;  the  patient was
then covered up moderately warm,  aud warm drinks given from
time to time to produce  and  keep up free perspiration, while the
parts most pained were fomented with  warm water, or  bathed  in
spirits.  Such, with slight modification, was the practice followed
by the writer of this article in the few first  cases that fell under his
care ; but an early observation of the happy influence of opium over
the extreme sufferings of the sick, led him ultimately to depend on
it exclusively, or nearly so, from the invasion to the termination  of
the attack ; and  the progress of the season, and the spread of the dis-
ease gave multiplied opportunities of noting the propriety and value
of the practice.   A  lady, in the seventh month of pregnancy, being
attacked by dengue, and  menaced most urgently with premature
labour, one hundred and twenty drops of tinct. opii were prescribed
immediately, and ordered to be repeated within  a  proper interval.
After three or four such  doses, she fell asleep, and awoke almost
entirely free from pain.   Another, within a few days  of her time,
was not only quieted in  a similar manner, but  absolutely relieved
from all inconvenience by the  same treatment; rising out of bed
the second day, going through the eruptive stage without illness or
suffering, and in ten days after being  delivered of a  fine healthy
child.   When summoned to a patient, it soon became his custom to
administer, without delay or preparation, such a dose of opiate as
seemed proportioned to and indicated by the  severity of the attack,
from a teaspoonful of common laudanum down to such  a lesser dose 
DICKSON ON DENGUE.
21
of this preparation, or of the tinct. of camphor, as was suited to the
age and other circumstances.   If the head was the seat of great pain
and  vehement  determination, cold affusion was made, or it  was
bathed with spirits, while the feet were immersed in hot water ; to
the swollen and suffering joints and limbs  warm fomentations  and
poultices were  applied.  The above dose of anodyne, which acted,
also, as  diaphoretic, was repeated at intervals of one or two hours,
until the symptoms were relieved, usually alone, sometimes, how-
ever, in combination with the acet. ammonise, a combination which
seemed applicable when the pains were less severe with a continuance
of heat and dryness of skin, and persistence of febrile excitement.
On the  return  of  pain or febrile  excitement, forming the second
stage as above described, the same remedies were again resorted to,
and with the same  advantage, controlling, as it seemed, the gastric
distress no less effectually than the arthritic pain and irritation.
   In comparing the several modes of treatment, it would seem fair
to remark that, if the patients subjected to the mild remedial  regi-
 men just detailed suffered no more at the time than those who were
 more actively  depleted by the lancet, and cathartics, and emetics,
 and passed through a convalescence not more protracted than those,
 they must certainly be considered as gainers, inasmuch as they  were
 put to far less annoyance and discomfort.   Yet it would not be too
 much to affirm, that the arthritic  pains which they endured  were
 more promptly relieved ; that they  underwent less constitutional
 derangement ; that they  fell  into a less degree of general debility,
 and consequently convalesced more rapidly ; and that, though they
 did not perhaps obtain the privilege of absolute exemption from the
 rheumatic pains, stiffness, and incapacity, which so long haunted
 every  community in which dengue had shown itself, yet they  were
 notably less subject than others to these inconveniences.
    In this  singular disorder, the local pains  usually preceded,  by
 periods of considerable length, any symptom of fever or constitu-
 tional  derangement.  Hours would  often intervene, during which
 the patient would limp through his usual occupation or amusement,
 and even eat heartily, and apparently digest well.  Cases, indeed,
 occurred, in which the whole of the first or quasi-rheumatic stage
 would be gone through in this way, and the nature  of the attack
 displayed at last, only by the breaking forth of the  characteristic
 eruption.   Now, it  would hardly be in accordance with received
 opinions, to affirm that the arthritic pains here were of an ordinary 
22
DICKSON ON DENGUE.
inflammatory nature ; obscure as they are, they may be regarded
as congestive, or simply irritative.   The opiate was here as applica-
ble as in the cold stage of an intermittent.  And even subsequently,
if fever did supervene, it did not seem to contra-indicate the opiate,
as being the effect of a peculiar and specific form  of inflammatory
irritation transient in duration, and  happily  determined by the na-
ture of its proximate cause to  external parts, or parts of no vital
importance.  In this early  stage, opium was, indeed, specially ser-
viceable.  All physicians were apt to resort  to the opiate in the
second stage, administering it freely in some form  of combination ;
the Dover's powder being a  general favourite.   But  although its
exhibition was even here of undoubted advantage, the golden op-
portunity for obtaining its highest benefit was past; the main object
of our art, the prevention of evil, was unaccomplished ;  the storm
had swept by, and its consequences were, with special difficulty, if
at all, remediable.  It is no easy matter to account for the  great
prostration of muscular strength and restorative energy so often left
by a paroxysm so transient, and not unfrequently so little violent in
degree, yet this circumstance constituted a prominent feature in the
history of the case under  consideration.  The contest was still to
be carried on.   We had to deal with an eruptive disease, and if the
forces of the constitution had been impaired, either by the intensity
of the attack, or by the remedies employed, as the lancet, cathartics,
antimonials, &c, the centrifugal determination which formed the
next essential step in its progress would be slow and imperfect, anJ
the stomach and other internal organs would  suffer in proportion.
At this juncture, many were tempted, by the great gastric uneasiness
and oppression, to direct purgatives of various quality,  mercurial,
saline, or  resinous, but usually with an  increase of the internal dis-
turbance,  a postponement of the period of cutaneous inflammation,
and a consequent protraction necessarily of  the duration  of the at-
tack.   This was attended, too, for  the most part,  with  an ultimate
aggravation of the  violence of the local pains, and an  increase of
their tendency to become fixed, and assume  a chronic inflammatory
disposition.  The  miserable stage of restlessness and oppression
was soonest ended  in those who remained  at rest in  a recumbent
posture, confining themselves to the lightest diet, and  avoiding all
exposure  to changes of temperature.  In the old and infirm, and in
such as had weakened  themselves, and given tenacity to the centri-
petal  determination, by the previous employment of improper medi- 
DICKSON ON DENGUE.
23
cines, it became necessary sometimes to resort to the highest order
of diffusible  stimulants, in addition to the opiate ; as camphor,
brandy, vol alkali and ether, with sinapisms to the epigastrium and
extremities.
  The vivid  eulogium which  Rush  passes upon the usefulness of
opium, in the somewhat similar affection described by him as occur-
ring in Philadelphia in 1780, is worthy of notice in this connection.
" Its salutary  effects in procuring sweat and a remission of the fever,
led me," he says, " to prescribe it in almost every case, and always
with the happiest effects.  Those physicians enjoy but little  plea-
sure in practising physic, who know not how much of the pain and
anguish in fevers of a certain  kind may be lessened by a judicious
use of opium."  In a more extended  experience  this benevolent
man would have been delighted to find that it  was entirely unne-
cessary, at least in a large majority of the  cases,  to wait for what he
styles '•' the proper evacuations," but that this relief or diminution
of pain and anguish might safely be accorded  to the patient at the
very commencement of the attack, and thus his severe sufferings
shortened  by many  hours, or lessened at once most notably in
degree.
   The writer will  be pardoned  for expressing, in conclusion,  his
belief that the profession has much to  learn upon the subject of the
admissibility of opium in the  treatment of fevers generally, and  for
 declaring, as he does with entire sincerity, that the most agreeable
 and satisfactory of all his experience in the healing art, has consisted
 in the employment of this divine remedy in states of the system,
 and under circumstances which dogmatists of all sects have  taught
 to offer positive contra-indications to its exhibition.
THE END.