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A new quartz spectrograph for absorption spectrophotometry is described. The method is a modification of the usual photographic method. A very wide spectrogram is divided into transverse comparison strips by means of a grid over the photographic plate, as first proposed by Jones. The instrument offers certain important advantages, among which are high speed, predetermined spectral distribution of absorption data, certainty of obtaining values at absorption maxima and other definite wave‐lengths, need for fewer photographic plates, and applicability to solids as well as to solutions and other liquids.

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In the discussion of suppurative labyrinthitis before this section at the Chicago meeting in June, 1908, it was my privilege and good fortune to present the first paper to appear in the medical literature of this country, reporting the recent progress made in the diagnosis and treatment of labyrinthine diseases, as taught in the Vienna schools. Since then the literature on this subject has been added to very materially, notably by Mac-Kenzie 1 of Philadelphia, Fridenberg, 2 and Richards 3 of New York, and Mr. Scott 4 of London, the last contributing some valuable new research data relating to the functions of the semicircular canals. 5 My first contribution was rather a foreword, very briefly outlining the methods of functional tests of the semicircular canal system developed by the researches of Barany, Alexander and Neumann of Vienna. The basis of these tests was founded on the fact that stimulation of

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The angular distribution of intensity of light scattered from a collimated beam incident upon a spherical air bubble in water is determined for any bubble with radius greater than a few wavelengths of the incident light. The computations are for wavelength 5893 A and n=1.3334, the relative index of refraction of water at 15°C. One external reflection, five internal reflections, and six refractions are considered. A general equation for the geometric attenuation factor is developed, with special forms for external reflection and for zero angle of incidence. The limits of accuracy of the equations for angles of scattering in the neighborhood of 0° and 180° are evaluated. The effects of diffraction and interference are assumed to be negligible. The fractions of the incident light scattered from each of the six “surfaces” (successive points of incidence of any ray on the spherical surface) are shown by accurate curves for all angles of deviation. The corresponding geometric attenutation factors are similarly shown. Final intensity values are tabulated and are plotted both with rectangular and with polar coordinates.

I wish to add my observations and experience to those of Blake, Reik, Holmes and others in perfecting the technic of the blod-clot dressing in mastoidectomy, a method, I feel, that is destined to revolutionize the after-treatment of mastoiditis. Recently in a historical review of the institutes of surgery, Sir Berkeley Moynihan1observed that "a discovery is rarely the work of one mind. It is one observation added to another that makes the supersaturated solution from which the crystal of truth at last precipitates." This observation was evoked by an allusion to the respective share or credit of Lister and Pasteur for the discovery of the antiseptic system. Moynihan added that "Lister never ceased to give credit to Pasteur for his share in the work that led finally to the development of the antiseptic method." The foregoing citation is peculiarly apropos to the theme of my text, since the

Lawrenceburg, Ky., Nov. 23, 1901. To the Editor: —The editorial and original articles in the issue ofThe Journalof November 16, discussing the enforcement of medical laws, are worthy the attention and approbation of every member of the profession in America. As a Kentuckian, I appreciate the tribute you pay to the profession of Kentucky in its effective work in ridding the state of quacks. Individually, however, on account of my recent experience in dealing with a quack, I am not so enthusiastic and feel that my efforts in protecting the profession and the public will hardly be so "strenuous" in the future as they have been in the past. Your suggestion that "what is needed to enforce the medical laws is a well-organized state society with its branches ramifying into every county and with a paid attorney of its own, to act for the profession, independent of, or

Although, since the time of Purkinje, vertigo from turning was known, and since the time of Florens, vertigo from syringing the ear with cold water has been frequently observed, it remained for Mach, Breuer and Ewald to note that vertigo is associated with nystagmus in man and with head rolling and nystagmus in animals. Since then, more exact observations by Alexander, by Kreidl, Kubo, Barany and Lange have led to important conclusions regarding the physiology of the semicircular canals, and shown how an overbalance of irritations of the semicircular canals of one side will produce nystagmus in man. Later, Stein, Krotoschiner, Panse and Mackenzie have further investigated the functions of the semicircular canals. Stein and Krotoschiner made use largely of the goniometer. Alexander and Mackenzie experimented with the gaits of patients, forward, backward and to the side; and for vertical movements by the aid of Alexander's goniometer. In this way

A method of measuring very high intensities in the focus of a highly convergent beam is described. A receiving cell with special stops is used to determine the energy distribution thermoelectrically. The sources of error with two different types of aperture are discussed. Errors due to heat radiated from the stop are minimized by using short exposures and by substituting a reflector for the stop immediately after the exposure. A suitable mount and adjusting mechanism for the cell are described.

Within the last few years, a number of workers in the field of medicine have expressed dissatisfaction with the methods commonly used in determining the amount of hemoglobin in the blood. They have pointed out not only that the different types of hemoglobinometer use different values of concentration of hemoglobin for 100 per cent on the scale, but also that the methods themselves are for the most part not sufficiently accurate for use in diagnosis. Of these two objectionable features, the latter is, of course, by far the more serious. The confusion and misunderstanding caused by dissimilar scale values can be avoided simply by the adoption of a uniform method of reporting hemoglobin, as recommended recently by Lindsay, Rice and Selinger; 1 but if the method itself is not sufficiently accurate, errors in diagnosis are unavoidable. ACCURACY OF METHODS IN COMMON USE In order to obtain some idea concerning the accuracy