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Part 2

Table of Contents


The Colonial Period (1607-1775)

Approach to an account of the beginnings of preventive medicine in America in the colonial period-an approach appropriate also to the first three quarters of the 19th century-is animated by the appraisal and sentiment expressed in another connection by Dr. Vannevar Bush (4):

A review of the mode of living of our forefathers, if it is to be useful, should be sympathetic in its attitude. The lapse of time often obscures the difficulties surrounding a former generation, and we are apt to smile at crudities when a just estimate should rather leave us to marvel that so much was accomplished with so little.

It is especially pertinent that we should review the technical accomplishments of another period only in the light of the contemporary science. Otherwise, we may well be guilty of a patronizing complacency, and as a result lose the benefit to be derived from a really analytical view of history.


The sources of prevailing ideas and examples of preventive medicine practices were essentially English. This was but natural. Colonial North America was an English possession and the population was predominantly British in origin. As Blake (5) has pointed out: "By and large they [the Colonies] had the same language, the same religion, the same inheritance of British social and political ideals. And by and large they had the same diseases."

In his characterization of the colonial times, Col. John van Rensselaer Hoff (6) emphasized the same point as follows:

From the beginning of the settlement of our country there was conflict not only between man and nature, but between man and


man. Every settler frorn the force of circumstances became a soldier, and while organization for military purposes was necessarily of the simplest character, there was such organization, and doubtless the medical man was a factor in it. As the population grew, the little wars took upon themselves more definite form, the more venturesome of the people organized themselves into bands or companies, and from time to time regular troops were sent from the mother country, with the organization then recognized as most satisfactory.

With the outbreak of the War of the Revolution all that our people knew of military affairs came from the British, and it was not unnatural that such organization as was contemplated for the American army was modeled on that of their foes.


Some of the "little wars" referred to by Colonel Hoff were fierce battles with the Indians; others were the colonial phases of large and prolonged European conflicts (7).

For these campaigns, the Colonies furnished unknown thousands of soldiers, millions of dollars, and large amounts of supplies. It has been stated that in the last intercolonial war, the provincial troops lost 30,000 men by disease or in battle (8) "-chiefly by disease, no doubt." Apparently, nothing new or important was contributed to military preventive medicine from the experiences of these wars. On the other hand, several men who became important in directing military hygiene in the Army of the United States in the American Revolutionary War were developed in these earlier wars (for example: John Morgan, John Jones, and above all, George Washington). In addition, according to Hindle (9):

* * * The most specific influence followed from the military experiences American physicians and surgeons had shared during the French and Indian War, which brought them in contact with British military medicine. The eyes of many were opened, especially of those who had had no academic training. They were exposed to a much better trained and organized profession in which certain standards of performance were insisted upon. All the Americans came to recognize more clearly their need of better education and


of regulations which would bar the incompetent from practice. War experiences coupled with post-war patriotism and enthusiasm for organizing led to surprising activity.


In Western Europe from 1740 to 1763, during the War of the Austrian Succession and the Seven Years' War, two great English Surgeons General, Sir John Pringle and Dr. Richard Brocklesby, consolidated doctrine and advanced military hygiene. They, and others, published in books their observations, conclusions, and recommended regulations for the preservation of the health of troops. Although these publications had little or no immediate influence upon military hygiene in the American Colonies, which at that time did not have a constituted army, slowly, within the decade and a half preceding the American Revolutionary War, these writings and teachings became known and available in Boston, New York, Philadelphia, and Charleston, South Carolina. The period from 1760 to 1775 was indeed a remarkable one in the history of American medicine in general and in relation to developments in military preventive medicine. As McDaniel (10) has stated:

   * * * During this period there returned to the Colonies of Pennsylvania, Massachusetts, Virginia, New York, Maryland, and South Carolina, armed with the Edinburgh M.D. degree, a group of young and ambitious physicians including such later distinguished medical figures as William Shippen, Jr., Benjamin Rush, John Morgan, Samuel Bard, Adam Kuhn, Arthur Lee, Gustavus Brown, Peter Fayssoux, and Walter Jones.

There were others: notably John Jones and Benjamin Church. Of these, Shippen, Rush, Morgan, Church, and John Jones held high and responsible positions in the Medical Department of the Army during the Revolution and were directly concerned with military hygiene during campaigns. They knew Sir John Pringle personally and had attended his medical dinner club meetings in London. Thus, they became familiar with ideas and practices of the best British military preventive medicine of the time.


FIGURE 1.- Sir John Pringle (1707-1782), founder of modern military preventive medicine and originator of the Red Cross concept; Surgeon General of the British Army, 1742-1758. He influenced the training of American physicians and surgeons who served in the Continental Army during the American Revolutionary War. (Portrait by Sir Joshua Reynolds, painted in 1775 (expression said to be unduly acidulous), copied from engraving in Pettigrew, T. J.: Medical Portrait Gallery * * * London & Paris: Fisher, Son, & Co., 1839, vol. II, 14th memoir. Courtesy of the Library of Congress.)

Sir John Pringle.-Sir John Pringle (1707-1782) (fig. 1), the founder of modern military medicine as distinguished from military surgery, and the originator of the Red Cross concept, studied medicine at Leyden under Boerhaave and Albinus. In 1742, several years after his return to England, he was appointed Surgeon General of the British Expeditionary Force in Silesia in the War of the


Austrian Succession. He was physician to the Earl of Stair, commander of the British forces on the Continent. It was through the Earl of Stair, at about the time of the battle of Dettingen in Bavaria in June 1743, when the army was encamped at Aschaffenburg, that Pringle brought about an agreement with the Duc de Noailles, the French commander, that the military hospitals on both sides should be considered as neutral, immune sanctuaries for the sick and wounded, and should be mutually protected. The International Red Cross, as constituted by the modern Geneva Conventions, developed from this conception and agreement, providing for not only humane treatment, but also a program for preventive medicine for prisoners of war, both sick and wounded, and able-bodied (11).

Pringle reformed military medicine and sanitation. Drawing upon his large experience in military hygiene, reinforced by systematic observations and research, he produced in 1752 (12) his "Observations on Diseases of the Army." This book soon became the most important book on military medicine of the time; and, as many of its elements have been incorporated in succeeding manuals and regulations, it has infused 20th-century writing on the subject. It contains, in fact, most of the principles and recommended preventive medicine practices of the present, except, of course, those that are based upon a knowledge of microbial causes of disease, of arthropod vectors and carriers-knowledge which was not experimentally determined until somewhat more than 100 years after Pringle wrote.

Pringle laid down rules of personal hygiene for soldiers. He emphasized the importance of adequate ventilation of barracks and hospital wards. He specified the essential requirements for proper clothing, for avoidance of overcrowding, for mitigation of exposure to heat, cold, wetness, and fatigue. Cleanliness, above all, was a requisite in his sanitary code, which comprehended the disposal of wastes of all kinds, the construction and care of latrines - "necessaries," as they were called - the selection of


campsites, the policing of camps, and the supervision and control of rations and drinking water. One of his associates in the period 1740 to 1748, in a campaign in the Netherlands, Francis Home (1719-1813), secured the issuance of an order that (13): "The dragoons shall drink no water without it be first boyled."

In a summary comment in his "Notes on the History of Military Medicine" (p. 149), Garrison stated: "Pringle-showed that jail fever and hospital fever are one and the same [later recognized as epidemic louseborne typhus fever]; did much for the better ventilation of shops, barracks, jails and mines; correlated the different forms of dysentery; and gave the name influenza to that dread disease. This work [the "Observations"], the source-book of all subsequent writers, was followed by Van Swieten's book on camp diseases (1758), and Richard Brocklesby's observations on military hospitals (1764)."

James Lind and scurvy.-At about the same time, the classical treatise (14) of James Lind (1716-1794) appeared concerned with scurvy and its prevention and cure by the inclusion of citrus fruits, or juices of oranges, lemons, or limes in the diet (fig. 2). This preventive measure, developed by Lind, among sailors also was applied among soldiers during the Revolutionary War.

Pringle's influence upon American civilian and military medical men was direct, personal, and literary. During Benjamin Franklin's stay in England on his first foreign mission from 1757 to 1762, he and Pringle became intimate friends, traveling companions, and correspondents. In 1755, Franklin had published in The Pennsylvania Gazette (15) Pringle's account of an occurrence of gaol fever. No doubt, during their travels together they discussed Franklin's modern-sounding theory of the contagiousness of colds and catarrhs (16): "I have long been satisfied [apparently since about 1744] from observations, that
* * * people often catch cold from one another when shut up together in close rooms, coaches, etc., and when sitting near and conversing so as to breathe in each other's transpiration; the disorder being in a certain state."


FIGURE 2.- James Lind (1716-1794), Surgeon in the Royal Navy (1739-1748); physician to the Royal Naval Hospital at Haslar (1758-1783); founder of naval hygiene in England and promoter of the use of citrus fruits and fresh vegetables to prevent and cure scurvy. He influenced practices of preventive medicine and nutrition among soldiers as well as sailors. (Pen drawing from a portrait by Sir George Chalmers, by A.E.A.H., reproduced in: Hudson, A. E. A., and Herbert, A.: James Lind * * *. J. Hist. Med. & Allied Sc. 11: 1-12, January 1956. Courtesy of the National Library of Medicine, photograph negative No. 52-661.)

Franklin was right in his ideas about one mode of transmission of colds and respiratory diseases, but knowing nothing about bacteria and viruses, he assumed incorrectly that the causative agent was "frouzy" air, corrupted, polluted, and rendered putrid by animal substances.


Pringle's observations and recommendations were addressed to officers of the army as well as to physicians. To him, in the 18th century, it was axiomatic, as it is to military authorities today, that the protection of health and maintenance of the health of troops are responsibilities of command, resting primarily upon nonmedical line officers.

Pringle, in his first edition of the "Observations," in 1752, coupled this basic administrative rule with the sage observation and advice (17): " * * * The prevention of diseases cannot consist in the use of medicine or depend upon any thing a soldier shall have in his power to neglect; but upon such orders as shall either appear unreasonable to him, or what he must necessarily obey."

Gerhard van Swieten.-Pringle was a friend and associate of Gerhard van Swieten (1700-1772) who among other accomplishments held the exalted position of physician to the Austrian imperial majesties, the dowager Empress Maria Theresa, and her son, Emperor Joseph II. As army surgeon, van Swieten published in 1758 an important book on the hygiene of troops and diseases incident to armies (18). The English translation published in 1762 was useful to medical men and line officers in the Army of the United States in the Revolutionary War. It was reprinted in Philadelphia in 1776 and in Boston in 1777.

Richard Brocklesby.-Richard Brocklesby (1722-1797) succeeded Sir John Pringle as Surgeon General of the British Army in Germany in 1758, and acquired wide experience during the next 5 years. In 1764, he published (19) his "Oeconomical and Medical Observations" in a book which ranks with Pringle's in laying down sound principles of hygiene for armies. Brocklesby insisted upon the good effects of discipline and minute attention to the laws of health as essential to the welfare of an army. He showed that soldiers must have plenty of fresh air in their rooms if they are to remain healthy. He drew up regulations for field hospitals, favoring small regimental hospitals rather than large general hospitals, as did Pringle


and all the great British Army surgeons of the 18th century. In that time, military hospitals were more dangerous to life than battles. These surgeons recognized that infections in hospitals could be reduced by keeping the sick and wounded scattered in small lots. Among the important military surgeons of the American Revolution who were influenced by Brocklesby was James Tilton, whose special design and construction of a small hospital "hut" will be described in connection with some events of the United States Army encampment at Morristown, New Jersey, in 1779 and 1780.

A sequel to Brocklesby's work, and an example of another British treatise on military hygiene which influenced Tilton and others, was Surgeon General Donald Monro's account of the means of preserving the health of soldiers on service, and of disease in the British military hospitals in Germany from 1761 to 1763 (20). While drawing heavily upon Pringle, Monro goes somewhat further in referring in detail to the Mosaic sanitary code, using the same passage from Deuteronomy (23: 12-14) that George Washington quoted in his General Order: Of Cleanliness, issued in 1777. (See figure 7, page 34, and appendix A, page 189.) Monroe included a special section about drinking water and "the means of correcting its bad qualities in camps." After mentioning the treatment of water with spirits, wine, vinegar, or cream of tartar, he wrote: "and if the water be previously boiled, it will be so much the better."


On 26 June 1721, about a month after the outbreak of an epidemic of smallpox in Boston, Zabdiel Boylston (1680-1766) introduced inoculation, or variolation, into the Colonies (21). On that day, in Boston, he inoculated his son and two of his Negro slaves. After they had recovered from the inoculated variola, he proved by exposing them to cases of smallpox that they were protected


FIGURE 3.- Cotton Mather (1663-1728), theologian and clergyman; interested in the scientific thought, natural philosophy, and medicine of the early 18th century. He stimulated Zabdiel Boylston to immunize against smallpox by inoculation (variolation) in Boston in 1721. This was the first positive achievement in preventive medicine in the Colonies. Mather has been called the first significant figure in American medicine. (Portrait from life by Peter Pelham, 1727, mezzotint. Courtesy of The New York Public Library.)

against the disease. Boylston took this bold action in response to the fervently stated and theologically supported advice of the Reverend Cotton Mather (1663-1728) (fig. 3). Immediately, a violent and prolonged controversy arose. The reasons were numerous - personal, political,


religious, and fear. By many citizens, inoculation was regarded as an impious act contrary to the will of God and as a dangerous source of spread of smallpox. Actually, it was an event of consequence in the history of American civil and military preventive medicine, marking the first deliberate active immunization of human beings against a specific communicable disease. Blake (22) has characterized it as " * * * the earliest important experiment in America in preventive medicine," and Beall and Shryock (23) have hailed it as "The Advent of Preventive Medicine: Boston, 1721."

The main events of the inoculation period, from 1721 to 1800, are so well known that they need not be recapitulated here. It is, however, pertinent to the theme of this volume to review a few of the occurrences and some of the theories, ideas, and observations of those times which were prophetic of the scientific preventive medicine of the 19th century. Particularly significant were the little-known views of Cotton Mather.


Inoculation against smallpox (the insertion into the skin of a normal individual, by scarification or puncture, of material from a fresh lesion of smallpox, with the intention to produce a mild attack of the disease) was an ancient practice of the Chinese and had been utilized in Africa since an uncertain time long past. It came to notice in England about 1700, and in 1714 and 1716, the Royal Society of London published in its "Philosophical Transactions" favorable accounts by Emanuel Timoni, of Constantinople, and Jacobus Pylarini, of Venice. In April 1721, the first inoculation in England was performed on the daughter of Lady Mary Wortly Montagu. Thereafter having been taken up by royalty and found relatively safe and a safeguard, inoculation became widely practiced in England and in Europe. It was applied in the British Army with increasing frequency before the start of the American Revolutionary War.



Himself a member of the Royal Society since 1713, Cotton Mather was familiar with the published letters of Timoni and Pylarini, and was impressed by them. They confirmed an opinion in favor of inoculation which he had formed "many months" before 1716 on the basis of stories told him by his "Guramantee-servant" (Onesimus), and by other Negro slaves, about the practice of inoculation in Africa. Mather, citing these sources, brought out the African evidence repeatedly in letters and pamphlets and most picturesquely in the manuscript of his never-published volume (24) "The Angel of Bethesda."

In "The Angel of Bethesda," Cotton Mather sets forth at some length his theory that smallpox was caused by "animalcula," stating a primitive germ-theory of disease which he derived largely from Benjamin Marten (25) and from his knowledge of the works of Athanasius Kircher Leeuwenhoek, and others. He speculated upon the implication of the vermicular, or animalcular, hypothesis of smallpox for immunology (26) and chemotherapy, although, of course, he did not use those terms.

Drawing upon the treatise of Bernardino Ramazzini (1633-1714), "De Morbis Artificum Diatriba" (Modena: 1700), he included in "The Angel" a section on occupational diseases. "Seeing how liable Mariners are to Scurvy," he wrote, "one cannot but encourage them in their Pease-Diet, and the use of Limons * * *." Furthermore, in his section, or discourse, on scurvy he noted that the disease occurred also among people on land: "Parts of America * * * have been of late years greviously infested with a disease called the Scurvy," and for prevention and cure "* * * an excellent thing for the Scurvy * * * is Whey, with the Juice of Orange or Lemon in it. Limons do Wonders, for the Releef of the Scurvy."



As soon as inoculation had been put into practice, it became a matter of vital importance to compare the risk of death involved in cases of naturally acquired smallpox with the risk of death in inoculated smallpox. Both Cotton Mather and Boylston saw the necessity and significance of the statistical approach to comparative mortality in the two conditions. Therefore, they kept records from which rates could be calculated, thereby providing "one of the first historical instances of the quantitative analysis of a medical problem." Crude at first, this procedure became refined as "the calculus of probabilities," chiefly by French mathematicians. In reporting this event, Shryock has commented upon its importance for preventive medicine, writing as follows (27):

One of the first to make use of a statistical comparison in the interest of preventive medicine [italics added] was the American clergyman, Cotton Mather. He reported to the Royal Society, during the severe Boston epidemic of 1721, that more than one in six of all who took the disease in the natural fashion died; but that out of three hundred inoculated, only about one in sixty died.

Early medical research in America was stimulated by the problems and phenomena of inoculation, as Garrison pointed out in a letter he wrote to Dr. E. C. Streeter on 9 April 1916 (28):

I have thought much about your plan of a medico-historical Bulletin and hope you and Cushing will put it through. You must look over these treasures in the Boston Medical Library-the unpublished Ms. of O. W. Holmes on Medical History, the medical letters of John Winthrop (Ms.) and the Ms. protocols of inoculation, showing that the colonial physicians in Massachusetts were working on the subject clinically and experimentally.

As "The Angel of Bethesda" was not published, there is no way of telling what influence it might have had upon the development of medicine in America. Various publications, including other writings of Mather, however, indicate that the ideas summarized above had a degree of currency. Some of these ideas became embodied in the doctrines of the military preventive medicine of the


colonial period. As will be shown in more detail later, inoculation against smallpox, introduced by Boylston and Mather in Boston in 1721, and applied to the Continental Army by George Washington in 1777, was an important factor in saving the Army from disintegration and in securing the successful outcome of the Revolutionary War.


During most of the half century, from 1725 to 1775, battles of the war between England and France were fought in North America. In these campaigns, the American Colonies supplied troop contingents to the British forces. As previously noted, American physicians and men who had become "doctors" through medical apprenticeship, or who had no medical training at all, became familiar with British military medicine and with British ideas and efforts for preserving the health of troops. Some of these Colonials became leaders in the local health activities of their communities, and some later occupied positions of responsibility in the medical organization of the Army of the United States in the Revolutionary War.


Also, during this half century, there were afflictions other than those of war. There was much sickness among the colonists due to endemic and epidemic diseases. The experiences contained lessons for the future Continental Army, but were not heeded sufficiently until several years after the start of the War for Independence. Smallpox appeared in several outbreaks ranging from clinically slight to severe. A severe and fatal one occurred in Charleston, South Carolina, in 1738, and a moderate one in Boston in 1761. The practice of inoculation, employed sporadically-sometimes permitted, sometimes prohibited-came to be supported by Benjamin Franklin, Dr. William Douglass, and other earlier opponents. By the time of the


Revolution, inoculation was practiced on general preventive grounds in the Colonies as it was in England (29).

Throughout the colonial period, there was anxiety over threats of yellow fever and plague, but neither disease appeared in epidemic form (30). A severe and deadly type of diphtheria killed hundreds of children and many adults in a widespread epidemic that lasted through 5 years, 1735-1740, in New England, New York, and New Jersey (31). Measles, long confused with smallpox (32), caused many deaths in New England from 1759 to 1772, was epidemic in Charleston, South Carolina, in 1722 and in Philadelphia in 1778. Scarlet fever occurred from time to time, but may be said to have been not as severe as it was in later epidemics. Intermittent fevers, probably malaria, were becoming widely distributed in the Colonies, occurring as far north as Maine in 1750. The chief causes of sickness and death from communicable diseases were diarrheas, dysenteries, and undoubtedly typhoid fever, which had not yet been differentiated from typhus fever.


An outbreak of communicable disease usually aroused the afflicted community to devise new measures for control or strengthen old ones. The major health activities were in control of contagion, chiefly by isolation of the sick and by quarantine of their contacts. In general, a partial list of protective measures applied by colonial communities, periodically and with very variable degrees of effectiveness, includes the following:

1. Sanitation.
     a.    Cleanliness: efforts directed toward the control of nuisances of filth and noxious trades.
     b.    Disposal of wastes-garbage, excreta, offal, etc.: efforts to prevent or remove bad odors.
     c.    Provision of water supplies: efforts to obtain "pure" water and to prevent pollution.
     d.    Drainage of swamps, marshes, and stagnant pools: efforts to prevent or eliminate miasmas.


2. Communicable disease control.
     a.    Quarantine.
               (1) Isolation of the patient at home.
               (2) Isolation of patients in pesthouses (the lazaretto system).
               (3) Maritime quarantine at ports.
     b.    Disinfection of the contaminated environment.
               (1) Explosions of gunpowder; fires in the streets; burning of tar or sulfur in houses.
               (2) Burning of contaminated clothing or bedding.
               (3) Exposure of imported materials to sunlight.
     c. Immunization-inoculation (variolation) for smallpox.

Evaluation of public health activities of the colonial period depends upon whether emphasis is placed upon administration or upon ideas. Emphasizing the former, Smillie (33) wrote in 1955:

In summary, public health administration during the Colonial period was not an important function of government. The community authorities selected temporary health committees in time of serious epidemic. These men acted as consultants, rather than administrators, and served only during the emergency. The enforcement of sanitary regulations, and the maintenance of community cleanliness as well, were not functions of the health officer but were the responsibility of the police authorities of the towns. In time of disaster, voluntary citizen associations did valiant service in caring for the sick poor, and as the cities grew in size, medical, hospital, and nursing care of the poor were provided for, in some degree, by the local government. But for the most part, these services were provided by charitable citizens and were not an official governmental function.

On the other hand, emphasizing the ideological aspects, Tandy (34) stated the case as follows:

Although there had been great developments in the field of medicine during the eighteenth century and a great improvement in popular intelligence to meet this advance in science, sanitary control was still based upon an insufficient body of biologic and medical fact. The etiology of disease was largely unrecognized and the breeding places of disease were undiscovered. The one hundred and fifty years of provincial regulation, however, show constant progress in the field of sanitation. The ideas and machinery which


were developed are suggestive of modern local commissioners and state boards of health. The colonial movement though still embryonic contained the seeds of our present highly developed intelligent direction of sanitary control.

The author of this volume agrees with both assessments and recognizes that the civilian conditions described in these evaluations were the sources of later events. They were among the factors that influenced the evolution of military preventive medicine in the United States Army.


At the close of the colonial period, two American medical schools were in operation. One was the Medical School of the College of Philadelphia, founded by Dr. John Morgan (fig. 4) in 1765, after his return from 5 years of post-graduate medical study in Europe (35). Later, this school became the School of Medicine of the University of Pennsylvania, which had been founded in 1735. In addition to Morgan, the faculty included Dr. William Shippen, Jr., Dr. Benjamin Rush, and Dr. Adam Kuhn, all of whom became high-ranking officers in the Hospital (the Medical Department) of the Continental Army at various times during the Revolutionary War.

The second institution was the Medical School established in 1768 at King's College (later Columbia University) in New York City. Both schools were closed during the Revolutionary War.

In the preface of his "Discourse Upon the Institution of Medical Schools in America" (p. xiii), Morgan mentions that after the end of his apprenticeship under Dr. John Redman he devoted himself "for four years to a military life, * * * being engaged the whole of that time, in very extensive practice in the [British] Army amongst diseases of every kind." Commissioned a first lieutenant, he served with the Pennsylvania militia in the army of General John Forbes in the campaign against Fort Duquesne in the French and Indian War. Through this he must have had some experience with British military hygiene of


FIGURE 4.- John Morgan (1735-1789), Director General and Physician in Chief of the Medical Department of the Army of the United States (1775-1777). An original proponent of medical education, he was a founder of the first Colonial medical school, in 1765, which became the School of Medicine of the University of Pennsylvania. (Portrait, courtesy of the Armed Forces Institute of Pathology, photograph negative No. WW-396.)

that time, but no details are given. In his prospectus for the new medical school, no provision is made for instruction in either civilian or military hygiene. The author of this volume has found no evidence that the Medical School of the University of Pennsylvania prepared men for work in public health and preventive medicine during the 10 years of its existence from its founding to the start of the Revolutionary War. Undoubtedly, however, Morgan's military experience with a British Army in the field was serviceable to him and to the American forces during the


period from 15 October 1775 to 9 January 1777 when he was Director General of the Medical Department of the Continental Army.


In 1874, Toner (36) estimated from a compilation of lists of names, that on the eve of the American Revolution (1775) there were about 3,500 established medical practitioners in the Colonies. Of these, approximately 400 had received formal medical training, about 50 of them holding M.D. degrees from the two American medical schools and about 350 holding degrees, some medical and some nonmedical from foreign universities and medical schools in London, Edinburgh, Leyden, Paris, and from American colleges. The remainder of medical practitioners had come into the profession through serving apprenticeships under physicians and surgeons, particularly doctors in Boston, New York, Philadelphia, Baltimore, and in Charleston, South Carolina. Among these "medical men," a few had had some experience in civilian sanitation and public health. These were men who had served as health officers, quarantine officers, or as members of community health committees of colonial towns and cities. As previously mentioned, a few had been in contact with British military hygiene during the French and Indian War. The leaders were men of ability, well informed in the medical and hygienic knowledge of the time, as far as it went. In their attempts to prevent and control infectious diseases, all were handicapped by the sheer lack of knowledge, undiscovered, of the causes, or etiology, of these diseases. In addition, deficiencies, incompetence, ignorance, poor discipline and low morale were distressingly frequent among most of the men whose services would be needed in the preservation of the health of troops in the event of war.