Pub Date : 1923-06-01DOI: 10.1109/JOAIEE.1923.6593534
Frederick A. Mott, L. A. Jones
The Eastman Theatre and School of Music was designed and given to the people of Rochester by Mr. George Eastman for the purpose of teaching and presenting music in its best form and under ideal conditions, using motion pictures as a part of the educational scheme. A great deal of preliminary work was done in planning the auditorium and the lighting to be used during the exhibition of motion pictures so as to eliminate all possibility of visual fatigue. Illumination and Brightness Measurements. From preliminary investigations on a small scale, it was found that fairly high illumination levels can be obtained in the motion picture theatre without any detrimental effect upon the quality of the projected picture. In planning the lighting system of this theatre, an attempt was made to obtain illuminations of fairly high values distributed so as not to cause loss of quality in the picture. Equipment. The electrical installation of a modern theatre, of the size and scope of the Eastman, together with a School of Music embraces a variety of equipment and apparatus. Alternating current is used for the lights and constant speed motors, and direct current for the variable speed motors. The chandelier is equipped with a system of indirect lights, decorative candles, direct lights, and lights for scintillating the crystals. The picture booth is equipped with two sources of direct current one source from the street main, and another from a motor generator set driven by alternating current. The outside illumination consists of a flood lighting system for the entire facade of the building, marquise lights and display and attraction signs. There are six separate telephone systems in this installation — the outside bell system, automatic inside system, a production phone system in the Theatre and another in Kilbourn Hall, the ushers and ticket office system and the dressing room system. Time clocks are installed throughout the institution and a program clock operates buzzers in all studios. There is an employees' and a watchman's time recorder and time stamp system for keeping account of the time spent in the piano and organ practice rooms. A set of chimes in the corridors notify the audience when the intermissions are over. A complete local fire alarm system is installed and also boxes on the Theatre and Kilbourn Hall stages in connection with the city system. Speed indicators at the stage directors stand, music directors stand and organ console indicate the speed of the film and telegraph indicators similar to a marine engine room telegraph provide means for signalling the projectionist. A magnetic douser or system of magnetically controlled shutters provides means of instantaneously changing from one picture machine to another as the end of the reel is reached. Finally, a radio broadcasting station is installed for distributing the musical productions throughout the country and thus fulfilling the aim of this institution which is to promote the education in and
{"title":"The electrical and illuminating equipment of the Eastman Theatre and School of Music","authors":"Frederick A. Mott, L. A. Jones","doi":"10.1109/JOAIEE.1923.6593534","DOIUrl":"https://doi.org/10.1109/JOAIEE.1923.6593534","url":null,"abstract":"The Eastman Theatre and School of Music was designed and given to the people of Rochester by Mr. George Eastman for the purpose of teaching and presenting music in its best form and under ideal conditions, using motion pictures as a part of the educational scheme. A great deal of preliminary work was done in planning the auditorium and the lighting to be used during the exhibition of motion pictures so as to eliminate all possibility of visual fatigue. Illumination and Brightness Measurements. From preliminary investigations on a small scale, it was found that fairly high illumination levels can be obtained in the motion picture theatre without any detrimental effect upon the quality of the projected picture. In planning the lighting system of this theatre, an attempt was made to obtain illuminations of fairly high values distributed so as not to cause loss of quality in the picture. Equipment. The electrical installation of a modern theatre, of the size and scope of the Eastman, together with a School of Music embraces a variety of equipment and apparatus. Alternating current is used for the lights and constant speed motors, and direct current for the variable speed motors. The chandelier is equipped with a system of indirect lights, decorative candles, direct lights, and lights for scintillating the crystals. The picture booth is equipped with two sources of direct current one source from the street main, and another from a motor generator set driven by alternating current. The outside illumination consists of a flood lighting system for the entire facade of the building, marquise lights and display and attraction signs. There are six separate telephone systems in this installation — the outside bell system, automatic inside system, a production phone system in the Theatre and another in Kilbourn Hall, the ushers and ticket office system and the dressing room system. Time clocks are installed throughout the institution and a program clock operates buzzers in all studios. There is an employees' and a watchman's time recorder and time stamp system for keeping account of the time spent in the piano and organ practice rooms. A set of chimes in the corridors notify the audience when the intermissions are over. A complete local fire alarm system is installed and also boxes on the Theatre and Kilbourn Hall stages in connection with the city system. Speed indicators at the stage directors stand, music directors stand and organ console indicate the speed of the film and telegraph indicators similar to a marine engine room telegraph provide means for signalling the projectionist. A magnetic douser or system of magnetically controlled shutters provides means of instantaneously changing from one picture machine to another as the end of the reel is reached. Finally, a radio broadcasting station is installed for distributing the musical productions throughout the country and thus fulfilling the aim of this institution which is to promote the education in and","PeriodicalId":268640,"journal":{"name":"Journal of the American Institute of Electrical Engineers","volume":"os-29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1923-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127772855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1923-05-11DOI: 10.1126/science.57.1480.550
Forty-two men, representing the manufacturers and users of traffic signals, federal and state governmental departments, associations interested in the prevention of traffic accidents, and representatives of the general public, are now at work on the drafting of a national code on the proper colors for traffic signals, which it is expected will not only cut down the annual loss of life through traffic accidents, but will eliminate many of the existing irritations to motorists and to the operators of steam and electric railways.
{"title":"Standardization of traffic signal colors","authors":"","doi":"10.1126/science.57.1480.550","DOIUrl":"https://doi.org/10.1126/science.57.1480.550","url":null,"abstract":"Forty-two men, representing the manufacturers and users of traffic signals, federal and state governmental departments, associations interested in the prevention of traffic accidents, and representatives of the general public, are now at work on the drafting of a national code on the proper colors for traffic signals, which it is expected will not only cut down the annual loss of life through traffic accidents, but will eliminate many of the existing irritations to motorists and to the operators of steam and electric railways.","PeriodicalId":268640,"journal":{"name":"Journal of the American Institute of Electrical Engineers","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1923-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125509621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1923-05-01DOI: 10.1109/joaiee.1923.6594115
C. Hoxie
The name pallophotophone has been given to a new device used both for permanently recording speech in a wavy trace on a moving photographic film, and for transforming the air vibrations of sound into exactly corresponding electrical vibrations for transmission directly, for example, to wireless broadcasting generators. The syllables “pallo” of this new word are taken from the Greek and with the following syllable indicate “dancing light.” This particular function, involving a rapidly vibrating beam of light, seems to be the most distinctive one of the combination. To explain the operations briefly perhaps it would be more illuminating to start with resemblances and differences as compared to the well known telephonic devices and talking machines. The dark wavy trace, Fig. 6a, on the films corresponds to the wavy spiral of the victrola disk. “There is the resemblance.” With proper translating means either device can reproduce the sounds recorded. In the translating mechanism is the difference between the two methods of recording speech. The victrola employs a needle set into vibration at one end of a lever, the other end of which is attached to the central point of a thin disk of mica. On the other hand, the dark wavy trace on the photographic film, moved in front of a slot, allows variable amounts of light to fall on a photo-electric cell. In turn, the photo-electric cell varies the electric current passing through it in direct proportion to the change in light. The lower diagram of Fig. 11 shows this arrangement. The human ear cannot hear the wavy light, neither can it hear the variations of current in the photo-electric cell, but if the variations of current are passed into a telephone receiver or loud speaker, either directly or through the intermediary of wireless waves, the diaphragm of the telephone transforms the electric vibrations into air vibrations of sound — “and there you are.” As compared to the simple mechanism of Edison's talking machine, the pallophotophone seems to traverse a wide detour. Each, however, has its particular uses. The pallophotophone has its marked advantages — some of which are quite evident and others hidden until explained. When the artist is available and at the broadcasting studio the pallophotophone dispenses with the record on a film and passes the energy of speech and music to light vibrations, and thence electric vibrations which pass directly to the wireless generators. Important to note, there are no microphones or other telephonic devices involved in these transformations. Nevertheless, the nearest analogous operation to the pallophotophone transmitter is in the familiar telephone transmitter. The telephone has a mouth-piece at the end of which is a diaphragm which vibrates with the sound waves. So also has the pallophotophone. However, its diaphragm is much lighter in weight. But from there on the resemblance disappears. The diaphragm of the telephone receiver pushes against loose particles of carbon a
{"title":"The pallophotophone","authors":"C. Hoxie","doi":"10.1109/joaiee.1923.6594115","DOIUrl":"https://doi.org/10.1109/joaiee.1923.6594115","url":null,"abstract":"The name pallophotophone has been given to a new device used both for permanently recording speech in a wavy trace on a moving photographic film, and for transforming the air vibrations of sound into exactly corresponding electrical vibrations for transmission directly, for example, to wireless broadcasting generators. The syllables “pallo” of this new word are taken from the Greek and with the following syllable indicate “dancing light.” This particular function, involving a rapidly vibrating beam of light, seems to be the most distinctive one of the combination. To explain the operations briefly perhaps it would be more illuminating to start with resemblances and differences as compared to the well known telephonic devices and talking machines. The dark wavy trace, Fig. 6a, on the films corresponds to the wavy spiral of the victrola disk. “There is the resemblance.” With proper translating means either device can reproduce the sounds recorded. In the translating mechanism is the difference between the two methods of recording speech. The victrola employs a needle set into vibration at one end of a lever, the other end of which is attached to the central point of a thin disk of mica. On the other hand, the dark wavy trace on the photographic film, moved in front of a slot, allows variable amounts of light to fall on a photo-electric cell. In turn, the photo-electric cell varies the electric current passing through it in direct proportion to the change in light. The lower diagram of Fig. 11 shows this arrangement. The human ear cannot hear the wavy light, neither can it hear the variations of current in the photo-electric cell, but if the variations of current are passed into a telephone receiver or loud speaker, either directly or through the intermediary of wireless waves, the diaphragm of the telephone transforms the electric vibrations into air vibrations of sound — “and there you are.” As compared to the simple mechanism of Edison's talking machine, the pallophotophone seems to traverse a wide detour. Each, however, has its particular uses. The pallophotophone has its marked advantages — some of which are quite evident and others hidden until explained. When the artist is available and at the broadcasting studio the pallophotophone dispenses with the record on a film and passes the energy of speech and music to light vibrations, and thence electric vibrations which pass directly to the wireless generators. Important to note, there are no microphones or other telephonic devices involved in these transformations. Nevertheless, the nearest analogous operation to the pallophotophone transmitter is in the familiar telephone transmitter. The telephone has a mouth-piece at the end of which is a diaphragm which vibrates with the sound waves. So also has the pallophotophone. However, its diaphragm is much lighter in weight. But from there on the resemblance disappears. The diaphragm of the telephone receiver pushes against loose particles of carbon a","PeriodicalId":268640,"journal":{"name":"Journal of the American Institute of Electrical Engineers","volume":"292 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1923-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115766653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1923-05-01DOI: 10.1109/JOAIEE.1923.6594112
B. PotterWilliam
The development of rail transportation since the day of stage-coaches and horsedrawn tram cars, has been a process of evolution in which some reminders of the past are still noticeable.
自从马车和马车时代以来，铁路运输的发展一直是一个演变的过程，其中一些过去的提醒仍然很明显。
{"title":"Observations on electric railway practise","authors":"B. PotterWilliam","doi":"10.1109/JOAIEE.1923.6594112","DOIUrl":"https://doi.org/10.1109/JOAIEE.1923.6594112","url":null,"abstract":"The development of rail transportation since the day of stage-coaches and horsedrawn tram cars, has been a process of evolution in which some reminders of the past are still noticeable.","PeriodicalId":268640,"journal":{"name":"Journal of the American Institute of Electrical Engineers","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1923-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126881608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1923-04-01DOI: 10.1109/JOAIEE.1923.6593330
G. Moore
It is the intent of this discussion to present, as simply as possible, a logical and fully reliable method for computing the “fixed charge” portion of commodity rate schedules. The hypothesis that the Service plus Quantity principle in rate-making is widely applicable, even far beyond the field of utility rates, emphasizes the necessity for an equitable basis for the computation of both portions of this dual rate structure. Moreover, since the billings of many customers, if computed strictly according to the cost of service, would be only negligibly affected by their Quantity use, the Service portion of their charge becomes of prime importance. The widely-used Peak Responsibility method, while undoubtedly a first approximation to the correct procedure, leads at times to gross inequity. The Eisenmenger method, while technically exact, is tedious in application. The Multiple Plant method, here presented for the first time, is believed to combine the virtues and eliminate the vices of both these methods. Moreover, since the Service plus Quantity principle was found to control in so remote a field as the freight schedule for car lots of logs, it is entirely possible that the simple and equitable analysis outlined below, may, with proper adaptations, become standard in a wide variety of commodity rate-schedule computations.
{"title":"The multiple plant method for the equitable apportionment of fixed charges","authors":"G. Moore","doi":"10.1109/JOAIEE.1923.6593330","DOIUrl":"https://doi.org/10.1109/JOAIEE.1923.6593330","url":null,"abstract":"It is the intent of this discussion to present, as simply as possible, a logical and fully reliable method for computing the “fixed charge” portion of commodity rate schedules. The hypothesis that the Service plus Quantity principle in rate-making is widely applicable, even far beyond the field of utility rates, emphasizes the necessity for an equitable basis for the computation of both portions of this dual rate structure. Moreover, since the billings of many customers, if computed strictly according to the cost of service, would be only negligibly affected by their Quantity use, the Service portion of their charge becomes of prime importance. The widely-used Peak Responsibility method, while undoubtedly a first approximation to the correct procedure, leads at times to gross inequity. The Eisenmenger method, while technically exact, is tedious in application. The Multiple Plant method, here presented for the first time, is believed to combine the virtues and eliminate the vices of both these methods. Moreover, since the Service plus Quantity principle was found to control in so remote a field as the freight schedule for car lots of logs, it is entirely possible that the simple and equitable analysis outlined below, may, with proper adaptations, become standard in a wide variety of commodity rate-schedule computations.","PeriodicalId":268640,"journal":{"name":"Journal of the American Institute of Electrical Engineers","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1923-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125224592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1923-04-01DOI: 10.1109/T-AIEE.1923.5060868
E. B. Craft, L. Morehouse, H. Charlesworth
From the earliest forms of telephone switchboards to the modern types, the development of the switchboard has been marked by the increasing use of automatic methods to supplement the manual operation wherever this would result in better service to the public or more efficient operation. In addition to all that has been done in developing and introducing automatic operations with manual switchboards, it has been found desirable and practicable to go further in the direction of introducing automatic operation in the telephone plant and a machine switching system has been developed in which the bulk of the connections are established without the aid of an operator. The complexity of a large metropolitan area and the exacting requirements which a machine switching system must meet are outlined briefly, and the system which has been developed to meet these requirements is described. The application of the system to a typical large metropolitan area and the means provided for permitting its gradual introduction into the existing plant are discussed.
{"title":"Machine switching telephone system for large metropolitan areas","authors":"E. B. Craft, L. Morehouse, H. Charlesworth","doi":"10.1109/T-AIEE.1923.5060868","DOIUrl":"https://doi.org/10.1109/T-AIEE.1923.5060868","url":null,"abstract":"From the earliest forms of telephone switchboards to the modern types, the development of the switchboard has been marked by the increasing use of automatic methods to supplement the manual operation wherever this would result in better service to the public or more efficient operation. In addition to all that has been done in developing and introducing automatic operations with manual switchboards, it has been found desirable and practicable to go further in the direction of introducing automatic operation in the telephone plant and a machine switching system has been developed in which the bulk of the connections are established without the aid of an operator. The complexity of a large metropolitan area and the exacting requirements which a machine switching system must meet are outlined briefly, and the system which has been developed to meet these requirements is described. The application of the system to a typical large metropolitan area and the means provided for permitting its gradual introduction into the existing plant are discussed.","PeriodicalId":268640,"journal":{"name":"Journal of the American Institute of Electrical Engineers","volume":"18 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1923-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125748229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1923-04-01DOI: 10.1109/JOAIEE.1923.6593328
F. Jeffrey
Tube Mill Characteristics THE greatest problem presented in the application of the electric motor for the individual drive of the tube mill is found in the fairly large torque required to bring it from rest up to its full operating speed. When once up to speed the load is practically constant, and only slight pulsations in the power requirements can be noticed.
{"title":"Application of electric motors for driving tube mills","authors":"F. Jeffrey","doi":"10.1109/JOAIEE.1923.6593328","DOIUrl":"https://doi.org/10.1109/JOAIEE.1923.6593328","url":null,"abstract":"Tube Mill Characteristics THE greatest problem presented in the application of the electric motor for the individual drive of the tube mill is found in the fairly large torque required to bring it from rest up to its full operating speed. When once up to speed the load is practically constant, and only slight pulsations in the power requirements can be noticed.","PeriodicalId":268640,"journal":{"name":"Journal of the American Institute of Electrical Engineers","volume":"193 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1923-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123333512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1923-04-01DOI: 10.1109/JoAIEE.1923.6593322
A. H. Babcock
WHENEVER electrification of steam railways on a large scale is advocated, one of the principal arguments advanced is the large saving in fuel sure to result therefrom; in fact, this was the initial point of attack in the early days of the art — the early 1890's, for example — long before overtime of train and engine crews had become the very real expense in train operation it is today. Many attempts to get accurate information on locomotive fuel consumption have been made during the intervening years, for comparison with known electric locomotive performance.
{"title":"Some fuel determinations made on locomotives operated by the Southern Pacific system","authors":"A. H. Babcock","doi":"10.1109/JoAIEE.1923.6593322","DOIUrl":"https://doi.org/10.1109/JoAIEE.1923.6593322","url":null,"abstract":"WHENEVER electrification of steam railways on a large scale is advocated, one of the principal arguments advanced is the large saving in fuel sure to result therefrom; in fact, this was the initial point of attack in the early days of the art — the early 1890's, for example — long before overtime of train and engine crews had become the very real expense in train operation it is today. Many attempts to get accurate information on locomotive fuel consumption have been made during the intervening years, for comparison with known electric locomotive performance.","PeriodicalId":268640,"journal":{"name":"Journal of the American Institute of Electrical Engineers","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1923-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116200861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1923-04-01DOI: 10.1109/JOAIEE.1923.6594117
F. H. Riddle
Plant control check tests are of importance primarily to the manufacturers of a product. These tests are, however, of considerable importance to the consumer. The lower a manufacturer's losses are, the cheaper his production costs will be. As high losses are caused by defects in the product it is evident that the fewer pieces there are with noticeable defects in them, the fewer pieces there will be that have minor defects in them that will escape detection even with the most careful inspection. Tests that will pick out the pieces that have these minor defects are of great importance to the consumer. Porcelain should be non-porous and tests which will make it possible to cull porous pieces are of paramount importance. If the fuchsine dye penetration method is to be used for this porosity test the selection of the test specimens must be made in a definite and dependable manner. If the firing of the porcelain is not done in a uniform manner so that the location of the pieces most likely to be porous are definitely known the test of any one piece would be of no value and it would obviously be impossible to test every piece. Where a continuous car tunnel kiln is used and the cross sectional area is relatively small the selection of the proper test specimen is not only possible but has been used successfully for several years. A recent development for testing disk insulators comprises a mechanism for subjecting each of the insulators under test to a pull test of 5000 pounds for two minutes, and simultaneously subjecting the pieces to the high-frequency oscillator test. This eliminates any doubt as to whether the porcelain would resist the two tests when applied at once. A petrographic study of thin sections of various porcelains is of great interest, in fact it is essential if the manufacturer or consumer desires to know something of the structure of the product, the extent to which the pyrochemical reactions have progressed and what the variations are from time to time. Several photomicrographs of various types of porcelain are illustrated. These are selected from a wide variety of wares in order to show the various steps in the development of different qualities of porcelain. The unlike thermal expansion and contraction of various porcelain ingredients is undoubtedly the cause of some of the deterioration of aged porcelain. It is evident that if some of the particles in the porcelain are under stress due to their tendency to contract more than the surrounding glassy matrix during cooling, after firing, there will be a tendency for these particles to rupture and break down in order to relieve this local strain. One of the illustrations shows this very well. Overfiring causes the development of gases in the body at a stage when the glassy matrix is in a molten condition. Continued firing causes expansion of the gases and results in the development of a vesicular structure. The degree of overfiring governs the size of the vesicles and the extent to whic
{"title":"The production of Porcelain for electrical insulation — VII","authors":"F. H. Riddle","doi":"10.1109/JOAIEE.1923.6594117","DOIUrl":"https://doi.org/10.1109/JOAIEE.1923.6594117","url":null,"abstract":"Plant control check tests are of importance primarily to the manufacturers of a product. These tests are, however, of considerable importance to the consumer. The lower a manufacturer's losses are, the cheaper his production costs will be. As high losses are caused by defects in the product it is evident that the fewer pieces there are with noticeable defects in them, the fewer pieces there will be that have minor defects in them that will escape detection even with the most careful inspection. Tests that will pick out the pieces that have these minor defects are of great importance to the consumer. Porcelain should be non-porous and tests which will make it possible to cull porous pieces are of paramount importance. If the fuchsine dye penetration method is to be used for this porosity test the selection of the test specimens must be made in a definite and dependable manner. If the firing of the porcelain is not done in a uniform manner so that the location of the pieces most likely to be porous are definitely known the test of any one piece would be of no value and it would obviously be impossible to test every piece. Where a continuous car tunnel kiln is used and the cross sectional area is relatively small the selection of the proper test specimen is not only possible but has been used successfully for several years. A recent development for testing disk insulators comprises a mechanism for subjecting each of the insulators under test to a pull test of 5000 pounds for two minutes, and simultaneously subjecting the pieces to the high-frequency oscillator test. This eliminates any doubt as to whether the porcelain would resist the two tests when applied at once. A petrographic study of thin sections of various porcelains is of great interest, in fact it is essential if the manufacturer or consumer desires to know something of the structure of the product, the extent to which the pyrochemical reactions have progressed and what the variations are from time to time. Several photomicrographs of various types of porcelain are illustrated. These are selected from a wide variety of wares in order to show the various steps in the development of different qualities of porcelain. The unlike thermal expansion and contraction of various porcelain ingredients is undoubtedly the cause of some of the deterioration of aged porcelain. It is evident that if some of the particles in the porcelain are under stress due to their tendency to contract more than the surrounding glassy matrix during cooling, after firing, there will be a tendency for these particles to rupture and break down in order to relieve this local strain. One of the illustrations shows this very well. Overfiring causes the development of gases in the body at a stage when the glassy matrix is in a molten condition. Continued firing causes expansion of the gases and results in the development of a vesicular structure. The degree of overfiring governs the size of the vesicles and the extent to whic","PeriodicalId":268640,"journal":{"name":"Journal of the American Institute of Electrical Engineers","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1923-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128231615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1923-04-01DOI: 10.1109/JOAIEE.1923.6593331
M. Luckiesh, L. L. Holladay
The remark is often heard to the effect that daylight costs nothing. This is true outdoors, but obviously it costs considerably to enjoy daylight indoors. One of the writers has discussed this subject elsewhere∗ quite a number of years ago, with the hope that architects would give attention to this aspect of natural lighting. Inasmuch as no data on the subject have appeared, the writers undertook the task of computing the costs of natural lighting as at present practised and to compare these costs with those of adequate electric lighting.
{"title":"Illumination items: By the lighting and illumination committee: The cost of daylight","authors":"M. Luckiesh, L. L. Holladay","doi":"10.1109/JOAIEE.1923.6593331","DOIUrl":"https://doi.org/10.1109/JOAIEE.1923.6593331","url":null,"abstract":"The remark is often heard to the effect that daylight costs nothing. This is true outdoors, but obviously it costs considerably to enjoy daylight indoors. One of the writers has discussed this subject elsewhere∗ quite a number of years ago, with the hope that architects would give attention to this aspect of natural lighting. Inasmuch as no data on the subject have appeared, the writers undertook the task of computing the costs of natural lighting as at present practised and to compare these costs with those of adequate electric lighting.","PeriodicalId":268640,"journal":{"name":"Journal of the American Institute of Electrical Engineers","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1923-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126972782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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