The disease bore many names over the centuries—Galen called it "dropsy of the chamber pot." It eventually came to be known as "diabetes mellitus"—the first word of the name thanks to early descriptions of the disease by Greek physicians, and the second word thanks to an exclamation by Dr. Thomas Willis, a noted 17th-century English physician, anatomist, and physiologist (more about this part of the name later).

Accounts differ as to who first used the term diabetes. Some say it was Demetrius of Apamea, who in about 200 B.C. likened polyuria to the siphoning of wine between pots—a practice now called "racking," which has long been used during fermentation to remove the sediment of dead yeast and promote proper aging. Noting the excessive flow of urine in some individuals, Demetrius is said to have referred to the condition as diabetes—a Latin word whose origin was a Greek term meaning "a passer-through, a siphon."

Others ascribe the medical appropriation of the word to Aretaeus of Cappadocia, a second-century Greek physician who was the first to write extensively about the disease. He provided in one of his surviving texts a stark description of the consequences of the disorder—then still uncommon: "Diabetes is a wonderful affection, not very frequent among men, being a melting down of the flesh and limbs into urine. . . . The patients never stop making water, but the flow is incessant, as if from the opening of aqueducts. The nature of the disease then is chronic, and it takes a long period to form; but the patient is short-lived if the constitution of the disease be completely established, for the melting is rapid, the death speedy. . . . They pass urine with pain, and the emaciation is dreadful; nor does any great portion of the drink get into the system, and many parts of the flesh pass out along with the urine."

The "mellitus" part of the disease's name derives from the Latin word for "honey" and appears to have sprung from an exclamation by Thomas Willis, who called the disease the "pissing evil." Upon tasting the urine of a patient, he said it was "quasi melle aut saccharo imbutam, mire dulcescere" ("as if made from honey or sugar, to taste marvelously sweet"). Willis's rediscovery of the observations of Sushruta and Avicenna, among others, led to the distinction between diabetes mellitus and diabetes insipidus ("insipidus" meaning "tasteless"). The latter is now recognized as a totally distinct disease, arising from a failure of

In these notes from an 1813 lecture at DMS, James Goodwin recorded Dr. Nathan Smith's description of diabetes. To research this article, the authors—three of them undergraduates—deciphered hundreds of handwritten pages like this one.

Avicenna, who wrote about medicine 1,000 years ago, referred to a disease characterized by excessive and sweettasting urine. Diabetes bore many names over the centuries—Galen called it "dropsy of the chamber pot."

the pituitary gland to secrete a hormone called arginine vasopressin (also called antidiuretic hormone, or ADH).

The saccharine nature of the urine of people with diabetes mellitus appears to have first been probed experimentally by Dr. Matthew Dobson, an English physician of the late 18th century who was also the first to document hyperglycemia (an elevation of glucose, or sugar, in the blood), as well as glycosuria (an elevation of glucose in the urine). In his 1776 text Medical Observations and Inquiries, Dobson—evidently relying at least in part on gustatory analysis—wrote: "It appears... that a considerable quantity of saccharine matter [is] passed off by the kidneys, in this case of diabetes, and probably does so in every imbalance of this disease, where the urine has a sweet taste...It further appears that this saccharine

matter is not formed in the secretory organ but previously existed in the serum of the blood." Dobson's observation proved to be an important turning point in the understanding of diabetes mellitus.

The next significant discovery, about 20 years later, was the work of Dr. John Rollo, a surgeon in the British Royal Artillery. With Dr. William Cruickshank—an artillery surgeon, chemist, and apothecary—Rollo undertook a longitudinal study of one Captain Meredith, who weighed 232 pounds and suffered from intense polyuria and dehydration. While adjusting Captain Meredith's diet, the two doctors recorded the quantity and nature of the sugar in his urine and blood, relying in part on taste and in part on the degree of effervescence caused by the addition of yeast to his urine. Rollo showed that a diet rich in protein and fat (largely from animal sources) and low in carbohydrates—together with the administration of several medications, which are noted below—resulted in a substantial weight loss, the elimination of Meredith's symptoms, and the reversal of both his glycosuria and hyperglycemia.

Rollo's recognition of the role of obesity in the development of type 2 diabetes, and of dietary therapy in treating it, were key to the eventual unraveling of the mystery of the disease. He reported his observations on Captain Meredith (and one other officer) in a book titled An Account of Two Cases of the Diabetes Mellitus; it was published in 1797—the same year Dartmouth's medical school was founded by Nathan Smith. It appears, based on student notes from Smith's lectures between 1806 and 1816, that he drew heavily on Rollo's conclusions in his own teachings about the disease.

The earliest account of Smith lecturing on diabetes is found in medical student William Ellsworth's 1806 notes, which include an apothecary recipe for one of the medications prescribed by Rollo—"hepatised ammonia," a mixture of hydrogen sulfide (a chemical with a rotten-egg smell) and ammonium hydrosulfide (a salt).

"Diabeates" [sic] was the subject of Nathan Smith's "Lecture 18" during 1811-12, according to Calvin Gorham's student notebook. Gorham wrote that Smith, citing Rollo by name, recommended several of his therapies: low liquid intake, warm clothing, a diet heavy in meat, and several medications—including "tincture of cantharides" and "hydrogenated sulfuret of ammonia" (another name for "hepatised ammonia").