important meteorological instrument. It was not until a later period, namely, in 1676, that the variations in aërial moisture could be satisfactorily ascertained. In that year Coniers produced an hygrometer an appliance doubtless much inferior to those used in more recent times for the same purpose.

From the dates I have given to the present day, numerous thermometrical, barometrical, and hygrometrical observations, etc., have been made in various parts of the world, and as a result meteorology has been elevated to a science. By its aid our profession has been enabled to decipher the climatology of disease, and has thus drawn numerous and important prophylactic and therapeutical inferences. In addition thereto, it has been qualified to detect atmospherical conditions favoring the origin and spread of epidemic and contagious disorders. The resources of Hygiene and Chemistry have in many instances proved efficient in destroying terrene causes of disease, and thus prevented their co-operation with inimical conditions of the general atmosphere which are less under human control. The poison liable to be engendered by such combined influences is pestilential, and almost ungovernable except by natural agencies.

There is one meteorological principle which it appears to me has not been sufficiently observed in reference to its causation of disease. I refer to electricity, both atmospherical and terrestrial. The intensity of atmospherical electricity is found to vary with the hour of the day, and to vary with the season of the year. Professor Loomis informs us that there are two daily maxima of intensity, and

two daily minima, and that there is one annual maximum of intensity and one minimum. Can the human body be subjected to such variations in its surrounding atmosphere without jeopardy? Can electricity, when acting jointly with other aërial conditions, induce an insalutary atmosphere? Can this subtile power, operating either alone or in combination upon inanimate terrene bodies, thus induce an influence capable of exciting disease in man? Is terrestrial electricity nugatory in its effect upon the human economy? We have yet much to learn on these subjects, and they are worthy of more extended examination than they have hitherto received.

It would be an oversight were I not to allude in passing to electricity in other of its bearings as of interest to our profession. The agent referred to was recognized by the early philosophers, deriving its name from the Greek 2xTpov, signifying amber, so called because excited by friction upon that fossil. Thales of Miletus, Theophrastus, Pliny, and others referred to a few of its properties, but it was reserved for one of our calling, Dr. Gilbert of Colchester, about the year 1600, to inaugurate the science of electricity. In its development our countrymen have played an important part. Franklin exhibited many of the qualities of the imponderable agent, and established its identity with lightning, and practically utilized his discovery by the construction of rods adapted to protect buildings and vessels during thunder-storms. Morse has employed the same principle as a means for the transmission of intelligence; while Field, with commercial enterprise, has united in telegraphic communication continents di

vided by seas. Galvanism, a branch of natural philosophy kindred to that of electricity, owes its origin chiefly to Galvani, physician and professor of anatomy at Bologna, in 1791. An accident directed his attention to the subject. Some frogs, prepared for cooking, and designed for his invalid wife, were lying in his laboratory near an electrical apparatus which was in action. The limbs of the animals, happening to be touched with a scalpel, were instantly convulsed. His notice was directed to this phenomenon, and he was led to investigate its cause. On publishing his experiments, he announced as a discovery that the animal body possessed an inherent electricity of a specific kind. Shortly after came Valli and Fowler, while Volta inaugurated a new system of experiments with the galvanic or voltaic pile. Since their day other observers, with improved instruments, have developed an electro-galvanic current potent in the decomposition of various compounds, and a valuable adjunct to chemistry in many of its applications.

While electro-galvanism has proved of incalculable advantage to mankind in an indirect manner, as I have indicated, it has also become a direct source of value. Our profession has not been satisfied that a powerful agent, first philosophically described by the illustrious physician of Queen Elizabeth, and subsequently, in a modified form, by the Italian anatomist, should be appropriated solely by the more mechanical departments of science. Vital electricity has been made a subject of special study, and at the present day we possess elaborate treatises, based on exact knowledge, relating to electrical currents as

speeding through vegetable fibres and through animal tissues.

From electro-physiology has been deduced a practical branch of medicine: I refer to electro-therapeutics. The electric current, artificially induced, is now skillfully applied to the animal economy as a remedial agent, and may be so tempered as to suit diverse morbid conditions. We observe it inducing motion where there is palsy; sensation in anesthesia; anæsthesia in hyperæsthesia; imparting tone where there is atony, and, according to the degree of its intensity, causing either the gradual or sudden destruction of abnormal growths. In alluding to these branches of medicine we should not fail to recall the brilliant labors of our young countryman, Dr. Charles E. Morgan, whose premature decease the profession of this city has so recently been called upon to deplore.

It has been contended that the practice of medicine in our own day has been too freely divided into specialties. This division of labor, however, will doubtless conduce to the promotion of science and to the amelioration of disease. Nor is it a novel precedent. Herodotus states, as given by Black, that when "he made the tour of Egypt, every physician applied himself to the cure of a single disease only, by which means physicians abounded everywhere some professing the cure of the eyes, some of the head and teeth, some of external, and others of internal disorders."

We are not warranted in approving or in emulating such extreme dilution of labor; its adoption would weaken, not strengthen our skill. It seems

necessary, nevertheless, for a few individuals in every large community to concentrate their energies on special departments of medical science, and the plan as at present adopted seems the one best calculated to achieve the purpose designed by such concentration, and is an evident improvement upon the example of those forefathers who preceded us twentythree centuries. The specialists cannot expect to escape the shafts of satire. Hood has employed his genius against the aurists when, in his Tale of a Trumpet, he relates the cure performed by the itinerant pedler:

"There was Mrs. F.,

So very deaf,

That she might have worn a percussion cap,

And be knock'd on the head without hearing it snap;
Well, I sold her a horn, and the very next day

She heard from her husband at Botany Bay!"

Though hygiene and therapeutics have made many advancements, there is a limit to their progress. To say nothing respecting the prevention and cure of the graver acute diseases, how many chronic disorders are there, especially of the nervous system, for which prophylaxis and relief are almost sought for in vain. Can drug be found to smooth the wrinkled face of grief? Can herb revive the heart subdued with care? Can mineral, floating fleetly through the veins, chase out perplexities which corrode the brain? Can spirit, permeating every mortal cell, give tone to the crushed frame of proud ambition? Can gas or vapor enliven cast-down melancholy? Can elixir give bloom to the tidy housewife distracted by domestic anxieties? Can there on earth