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Bulletin of the Bureau of Standards

Results of research in science and technology at the National Bureau of Standards were reported in Scientific Papers. The first 14 volumes of the Scientific Papers were issued as the Bulletin of the Bureau of Standards. These volumes date from 1904 to 1919. The separate papers were called Reprints.



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This paper is an extension and revision of a previous paper by Rosa and Cohen. It is now by far the most complete and thorough study of the subject that has yet been published. The authors have taken great pains to bring it thoroughly up to date, and have made a critical study of nearly all the recent papers on the subject. The comparisons of the results obtained by various authors and the invcstigations of the convergence of the various series that have been proposed have cleared up the whole...
Topics: inductance, Condensed matter, electronic structure, electrical, magnetic, and optical properties
Formulae for the self and mutual inductances of straight wires and rectangles are to be found in various books and papers, but their demonstrations are usually omitted, and approximate formulae are often given as though they were exact. The author derives the expressions very simply from Laplace's formula instead of using Neumann's formula, and thus gives a much better physical view of their meaning. He also deduces some interesting new formulae. The assumption is made that the magnetic field...
Topics: inductance, Condensed matter, electronic structure, electrical, magnetic, and optical properties
Bulletin of the Bureau of Standards
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Bulletin of the Bureau of Standards
by Osborne, N.S.; McKelvy, E.C.; Bearce, H.W.
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Bulletin of the Bureau of Standards
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Bulletin of the Bureau of Standards
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The investigations carried out up to the present time on the equilibrium diagram of the iron-carbon system cannot b6 regarded as exhaustive, because in no case have the investigators worked with pure materials. On this account the authors have prepared a series of alloys containing 0.08 to 3.27% of carbon to serve as the basis for an accurate study of the thermal equilibrium of the Fe-C system. Pure iron has been made by the electrolysis of American ingot iron, and a detailed study has been...
Topics: metallography and properties and treatment of metals and alloys, Electrochemistry and...
A survey of previous researches on the refraction of air shows that many investigators have worked either with white light or with one monochromatic radiation, and dispersion measurements have been limited to a small interval of the spectrum. No index measurements exist for waves longer than those corresponding to orange light, and in the ultra-violet the dispersion formulae disagree by more than 10% of the refractivity. Accordingly it was deemed advisable to measure the absolute indices of...
Topic: light refraction
In magnetic measurements made at the Bureau of Standards it has been found that the heating effect of the current, employed to produce fields of 100 to 300 gauss, changes appreciably the value of the induction for a given field. The usual practice, when an accuracy of 1 % is desired, has been to immerse the coil in an oil bath maintained at a constant temperature of 25 degrees . The object of the present investigation is to determine the magnitude of the temperature effect and to see whether it...
Topics: magnetism, Magnetic properties and materials A4100 Electricity and magnetism, fields and charged...
Bulletin of the Bureau of Standards
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The authors criticise the statement made by Jaeger and Lindeck, that the variation of manganin resistances with atmospheric humidity need cause no anxiety to the owners of such resistances. In a particular case at the Bureau of Standards the variation of resistance of a standard coil between Jan, 1 and May 1, 1907, was about 85 parts in 100,000, the change occurring in the course of two weeks of damp weather, with the humidity averaging 64 per cent. The atmospheric conditions were not more...
Topics: apparatus and instruments, measurements and use of instruments, Condensed matter, electronic...
Bulletin of the Bureau of Standards
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The luminosity of a radiator is defined as the integral from O to infinity with respect to lambda of the product of visibility (V) and energy (J) of the radiating source, /b i,e./ int /sub 0//sup infinity / VJ/b d/ lambda V = /b f/( lambda ) is given by the experimental determinations of Ives, Nutting, and Hyde and Forsythe, and J = /b c/sub 1// lambda /sup -5//b e//sup -c//sub 2//sup lambda thetas / (Wien's law). The effective wave-length lambda L of the luminosity has been defined...
Topics: photometry, rays and radiation, temperature, Heat flow, thermal and thermodynamic processes
In this paper is treated the measurement of the "effective inductance" of non-inductive resistance coils for use in alternating-current bridges and in potentiometer circuits where it is desired to know the phase-angle. The latter depends on the inductance and the capacities between the windings and between the various parts of the coil and the earth. The "effective inductance" is that value of inductance which would produce the observed phase-angle. The measurements with...
Topics: inductance, measurements and use of instruments, Condensed matter, electronic structure,...
Bulletin of the Bureau of Standards
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When it is desired to determine the resistivity of a fairly large portion of earth extending to a considerable depth, and it is not possible to disturb the portion of the earth to be measured, the following method is applicable. Four holes, 1, 2, 3, 4, are made in the earth approximately uniformly spaced in a straight line. The diam, of the holes is not more than 10% of the distance /b a/ between them, and all holes extend to approximately the same depth /b b/, usually that depth at which we...
Topic: measurements and use of instruments/ B8000 Power systems and applications
Accurate measurements of wave-lengths and determinations of the characteristics of the emission lines in the spectra of the elements are of importance in spectroscopic analysis, and for the discussion of regularities in spectra. Securing such data about the long waves has been delayed chiefly by the insensitiveness of ordinary photographic plates to the red and adjacent infra-red spectral regions. More extensive use of photographic dyes is important for these spectral investigations. Dicyanin...
Topics: measurements and use of instruments, spectra
Bulletin of the Bureau of Standards
by Noyes, W.A.; Weber, H.C.P.
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Bulletin of the Bureau of Standards
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Topics: inductance, Electrical instruments and techniques
It is found that a close approximation to uniformity of magnetic flux along a test rod can be secured by using properly constructed specimens and yokes and properly distributed magnetising coils. The double bar and yoke form of magnetic circuit seems to offer the greatest number of advantages and the fewest disadvantages. The reluctance of the yoke and joints can be kept very small. This is accomplished by having the yokes short and of moderately large cross-section, and making the surface of...
Topics: magnetism, measurements and use of instruments, Magnetic properties and materials A4100 Electricity...
Bulletin of the Bureau of Standards
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After a consideration of the meaning of plastic as compared with viscous flow, the author goes on to describe experiments made to determine the laws governing the former. The different types of viscous and plastic flow are discussed theoretically. In the case of mixtures, according to circumstances the viscosities of the components may be additive, the fluidities may be additive (a special case of this is the suspension of solid in a fluid), or slipping or seepage may take place to modify the...
Topics: elasticity, viscosity, General Physics
Bulletin of the Bureau of Standards
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Bulletin of the Bureau of Standards
by Brooks, H.B.
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A method of testing instrument transformers by means of ordinary commercial testing instruments is described. It has to be remembered that from the practical point of view we need only take account of these errors in ratio or phase angle which produce a visible error in the reading of the indicating wattmeter. A wattmeter is taken and used in such a way that differences in ratio or phase angle of the transformer being tested and a standard transformer may be most readily detected. The method is...
Topics: transformers, rotary converters and boosters, measurements and use of instruments/ B8300 Power...
Bulletin of the Bureau of Standards
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Describes convenient methods for adjusting the Thomson bridge when very low resistances are measured. The adjustments are made without the repeated opening and closing of the low-resistance connection between the two low-resistance arms.
Topics: measurements and use of instruments, Condensed matter, electronic structure, electrical, magnetic,...
Bulletin of the Bureau of Standards
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This paper comprises a complete statement of previous formulae and includes the development of a more direct solution of the case where two parallel, coaxial, circular ceils are placed at such a distance that their mutual attraction or repulsion is a maximum. Methods for the application of the formulae, worked-out examples, and tables to facilitate calculation are given. The paper does not permit of a more detailed abstract.
Topics: electricity and magnetism, Condensed matter, electronic structure, electrical, magnetic, and...
An investigation undertaken to determine the advantages and limitations of platinum resistance thermometers at high temperatures, especially with reference to reproducibility of scale, method of calibration, formulae best expressing the relation between resistance and temperature, effect of impurities in the wire, and the most satisfactory methods of construction and use. These points are fully dealt with in the experimental investigation, and the following are among the conclusions arrived at:...
Topics: thermometry, pyrometry and calorimetry, Heat flow, thermal and thermodynamic processes
Bulletin of the Bureau of Standards
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This paper discusses the relations between (1) the operation constants, namely, the external critical resistance, the deflection and ballistic periods, and the sensitivity in the particular conditions for use in which the galvanometer is intended, and (2) the intrinsic constants, namely, the inertia, damping, restoring, and displacing constants and the resistance, for critically damped galvanometers. The best relations for these quantities for attaining the desired sensitivity whether to...
Topics: measurements and use of instruments, Condensed matter, electronic structure, electrical, magnetic,...
This paper refers to experiments carried out daring 1909-1910 between the Fesscnden high-power station at Brant Hock and the U.S. cruisers /b Birmingham/ and /b Salem/. A series of experiments enabled data to be obtained as to the laws governing the radiation and reception of electric waves, and the subject of atmospheric absorption up to a distance of 1000 miles to be studied. At Brant Rock 50 to 60 kw. were employed, the two ships' stations being equipped with 10-kw. 500-~ motor-generators. A...
Topics: radiotelegraphy, oscillations and waves (electric)/ B6210F Telegraphy
Platinum black, made by reducing a platinum solution with zinc or alkaline formate and then warming with dilute hydrochloric acid to remove iron, is made the anode of an electrolytic apparatus containing HCl. A divided cell is used, the Pt sheet kathode being contained in a porous pot. The apparatus is so arranged that the solution of chlorplatinic acid, which is specifically heavier than the remainder of the solution, is siphoned off as it is formed. In concentrating the solution so obtained...
Topics: electrolysis, Electrochemistry and electrophoresis
Bulletin of the Bureau of Standards
by Buckingham, E.
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Bulletin of the Bureau of Standards
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Bulletin of the Bureau of Standards
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Topic: table of contents
Bulletin of the Bureau of Standards
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Topic: table of contents
Bulletin of the Bureau of Standards
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Topic: Table of contents
A summary of the experiments made on the silver voltameter at the Bureau of Standards, together with a very brief account of recent work done elsewhere. In 1911 at the Russian Bureau at Petrograd experiments by M. Foehringer with the Smith voltameter resulted in the value 1.01830 int. volts at 20 degrees C. being assigned to the Weston normal cell. In 1916, Obata at To macr kyo macr , using the Smith voltameter, obtained the value 1.01827 int. volts at 20 degrees C. A specification is proposed...
Topics: electrolysis, measurements and use of instruments, Condensed matter, electronic structure,...
Bulletin of the Bureau of Standards
by Dickinson, H.C.; Osborne, N.S.
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specific heat and latent heat; Heat flow, thermal and thermodynamic processes
Topic: USA
This is a continuation of former papers, and consists of (1) an historical summary of the principal determinations up to the present of the value of the constant, sigma , of total radiation; (3) a new determination of by a method in which accurate corrections are made for lack of "blackness" of the radiator, for losses by reflections for variation of thickness of lampblack layer, and for atmospheric absorption. It is demonstrated that the presence of aqueous vapour in unmeasured...
Topics: rays and radiation, Heat flow, thermal and thermodynamic processes
Bulletin of the Bureau of Standards
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Bulletin of the Bureau of Standards
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Topic: index
Bulletin of the Bureau of Standards
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Gives some applications of the curve of visibility of radiation for the average eye (125 observers) to radiation problems. A mathematical equation is given of the average visibility curve. Using this visibility equation and Planck's equation of the black body, calculations are made of the luminous flux emitted by such a body at various temperatures, also the luminous efficiency, the Crova wave-length, and the mechanical equivalent of light. The visibility curve of the average eye gives the...
Topic: rays and radiation
Bulletin of the Bureau of Standards
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The colorimeter here described is a monochromatic analyser, and was designed to be a practical working instrument of wide range, high precision, and of great simplicity. It is so arranged that light of a pure spectral hue may be mixed with white light to match the unknown; or, in the case of purples, it is mixed with the unknown to match white. The match is made with a photometer cube. In the Fig., collimator 1 is movable; all the remaining parts are fixed. Collimators 1 and 4 with prism P form...
Topic: apparatus and instruments
wavemeters;Display, recording and indicating instruments
Topic: USA
Bulletin of the Bureau of Standards
by Hyde, Edward P.
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Bulletin of the Bureau of Standards
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Reviews the nature of the possible errors to which a micrometer microscope is liable and gives a table of the errors found in 5 specimen instruments. The author describes a method by which the corrections for progressive and periodic errors in such instruments as the microscopes of a transverse comparator may be made very readily, the microscopes having been calibrated once for all. The results of each calibration are embodied in a table giving directly for each tenth of a turn the total...
Topic: measurements and use of instruments
Bulletin of the Bureau of Standards
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The most obvious method of directly determining the inductance of a coil is that originally proposed by Joubert, and consists in first determining the impedance of the coil and then finding the ohmic resistance of the wire and the frequency of the current employed. In a variation of this method, described by Gray, a non-inductive resistance is placed in series with the coil whose inductance is to be measured, and an alternating current passed through both. By means of an electrometer the...
Topics: measurements and use of instruments, Condensed matter, electronic structure, electrical, magnetic,...
Bulletin of the Bureau of Standards
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Topic: Table of contents
This paper describes a number of measurements of both large and small inductances by Anderson's method, using (1) a battery as a source of current and a d'Arsonval galvanometer, with a rotating commutator to interrupt and reverse simultaneously the current and galvanometer terminals; or (2), what has proved more satisfactory, an alternating-current and a vibration galvanometer, the latter being tuned to the frequency of the current furnished by the generator. The method has been found rapid and...
Topics: measurements and use of instruments, Electrical instruments and techniques
Bulletin of the Bureau of Standards
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The first part of the paper is devoted to a description of apparatus including the spectrometers, radiometric appliances and rotating sector device; dispersion curves for various prisms of quartz, fluorite, rock-salt and carbon disulphide are also given. The author then proceeds to describe determinations of the emission curve of the acetylene flame under different conditions, including its comparison with incandescent solid substances such as the Nernst glower. He points out the distinction...
Topic: rays and radiation
Bulletin of the Bureau of Standards
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The initial part of the paper summarises past researches on the pentane lamp. Subsequently general instructions are given for the setting-up and operation of the lamp, and some experiences of the lamps in the United States summarised. A curve is given illustrating change in c.p. caused by varying height of flame, and special emphasis is placed on the avoidance of vitiation of the air, cooling air-currents, etc. Nevertheless it is believed that, with care, the values attained from any lamp can...
Topic: lamps and lighting/ B8530B Light sources
Bulletin of the Bureau of Standards
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It is known that the iron loss in a static transformer is dependent upon the wave-form of the applied e.m.f., and G. Roessler has shown experimentally that when the same effective value of the e.m.f. is applied to a transformer the iron losses are less when the e.m.f. wave is peaked. The present paper has been prepared with a view to a more through treatment of the question. The author assumes the iron losses to be given by the expression alpha /b n/ B/sup 1.6/ beta /b f///sup 2//b n//sup...
Topics: transformers, rotary converters and boosters, alternating-current research/ B8300 Power apparatus...
Bulletin of the Bureau of Standards
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The energy radiated by a black body and also by platinum is given by E = /b c//sub 1/ lambda /sup /b a// epsi -/b c//sub 2// lambda T...(1) and the shifting of the maximum of the energy curve by lambda /sub max./ T = const., the symbols having their usual meanings. The object of the investigation was to obtain some estimate of the emissivity of incandescent metal filaments, /b e.g./, tantalum, tungsten, and osmium, the assumption being made that their spectral energy distribution follows (1)....
Topics: rays and radiation, thermometry, pyrometry and calorimetry, Heat flow, thermal and thermodynamic...
The importance of the e.m.f. developed by the relative motion of the magnet and the winding of the galvanometer is pointed out and the general theory of the instrument is developed. The fundamental equation is stated and a solution is obtained giving the various working constants in terms of the intrinsic constants. The advantage of using a transformer with an instrument developing a relatively large back e.m.f. is shown. The double period sometimes observed is due to the system being...
Topics: measurements and use of instruments, Condensed matter, electronic structure, electrical, magnetic,...
Bulletin of the Bureau of Standards
by Cohen, L.
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The author obtains a complete solution of the problem of coupled circuits-direct-coupled circuits as well as those coupled electromagnetically-by a method which avoids the difficulty of getting the roots of a biquadratic equation. Both cases are fully worked out. The paper is altogether mathematical and cannot be abstracted.
Topic: oscillations and waves (electric)/ B7500 Medical physics and biomedical engineering
Bulletin of the Bureau of Standards
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Topic: table of contents
Bulletin of the Bureau of Standards
by Wolff, Frank A.
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Bulletin of the Bureau of Standards
by Fischer, L.A.
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measurements and use of instruments; General Physics
Topic: USA
A series of experiments has been carried out with the primary object of obtaining complete data to formulate specifications, according to which the voltameter might be used at any time for the measurement of current and (with the aid of resistance standards) for checking the constancy of the Weston normal cell. The voltameters used were the porous cup and Smith form, which were found to be in substantial agreement and give the value 1.01827 int. volts for the Weston normal cell at 20 degrees C....
Topics: electrolysis, measurements and use of instruments, Condensed matter, electronic structure,...
Bulletin of the Bureau of Standards
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1. Fraunhofer's A band (wave-length 0.760 mu) and a considerable region of greater wave-length have been photographed in numerous stellar spectra by means of plates sensitised with dicyanin. 2. A strong band at 0.760 mu, nearly coincident with A, has been discovered in spectra of Class M. It is very marked in Mb and Md spectra, and may be useful for purposes of classification. 3. The titanium arc shows flutings near this wave-length, which probably correspond to the stellar bands. 4. In spectra...
Topics: astronomy, photography, General Physics
Bulletin of the Bureau of Standards
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The author suggests that there is a need for some method of estimating the resemblance of artificial illuminants to daylight, /b i.e./, of determining their "daylight efficiency." Assuming that, by the extraction of certain qualities of light in an illuminant its colour could be brought to resemble that of daylight very closely, the daylight efficiency of a source might be expressed in the form (intensity of available white light)/(total intensity of source). The author suggests two...
Topics: photometry, lamps and lighting
Bulletin of the Bureau of Standards
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The object of the research was to separate the eddy-current loss in iron from the loss due to magnetic hysteresis, and determine whether the latter varies or is constant when the max. value of the magnetic flux is kept constant while the form of the wave is varied. By the application of Rossler's formula a separation of the losses may be approximately accomplished by measurements of the total losses at two frequencies and the same flux density. In order to obtain accurate results the following...
Topics: measurements and use of instruments, electrical engineering, magnetism/ B8000 Power systems and...
Bulletin of the Bureau of Standards
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The freezing-point of mercury was determined by means of resistance thermometers calibrated at 0 degrees , 100 degrees , and the sulphur boiling-point (444.6 degrees at normal pressure). Various precautions were observed to avoid errors due to impurities in the mercury, conduction along the leads, and the heating effect on the thermometers of the measuring current. The mean value - 38.873 degrees C. was obtained for the freezing-point, the max. deviation of any determination from the mean being...
Topics: freezing, melting and boiling points, Heat flow, thermal and thermodynamic processes
Bulletin of the Bureau of Standards
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Topic: table of contents
Bulletin of the Bureau of Standards
by Guthe, K.E.
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Bulletin of the Bureau of Standards
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Bulletin of the Bureau of Standards
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A full account giving all details.
Topic: apparatus and instruments/ B8000 Power systems and applications
Bulletin of the Bureau of Standards
by Dellinger, J.H.
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Bulletin of the Bureau of Standards
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It has been shown by Fisher and Austin that the radiation resistance of an antenna decreases rapidly with increasing wave-length to a minimum and then rises again in a linear manner with further increase in wave-length. This increase has been attributed by Austin to dielectric absorption in imperfect dielectrics in the electric field of the antenna. This explanation is verified by the tests now described. An experimental antenna was built in which the bad effects of poor dielectrics in the...
Topic: radiotelegraphy/ B6210 Telecommunication applications
Bulletin of the Bureau of Standards
by Coblentz, W.W.
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Particulars have been given of some tests on tubes containing helium with a view to their being used as standards of light. It was then found that small differences in thickness in the bore of the capillary tubes used introduced errors and more uniform tubes, which were also fairly free from striations, have since been obtained. Details of the photometric tests to which these tubes were subjected are given. The mean deviation in candle-power per cm. length of tube is found to be 1.15 per cent.,...
Topic: photometry
Bulletin of the Bureau of Standards
by Burgess, G.K.
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Bulletin of the Bureau of Standards
by Austin, L.W.
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