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Overhead systems reference book
BOOK
[J. F. I.
REVIEWS.
presenting it in satisfactory form compelled the division of the work into two parts and has delayed the appearance of the second part. The same principles of arrangement followed in the first part have been In this present issue the reader will applied in the preparation of the second. find many examples paragraphs which References are also Almost everywhere secondary particles of colloid solutions the composition of
of the progress in knowledge on this subject and many are appendixes to the data given in the previous volume. made to data in the third and fourth editions of the work. one finds references to the significance of the primary and (monone and polyone) for the structure and characteristics and also the results of the exact investigation concerning the particles.
The preparation of the volume has been materially expedited by the services of collaborators whose work is gracefully acknowledged in the preface. Among these are Prof. Dr. Handovsky, of GGttingen, whose contributions are in the department of egg albumin colloids, and Doctor Thiessen, also of Gijttingen, who has contributed to the article on soap as well as certain other chapters. Several of the collaborators have been especially helpful in connection with proof-reading and credit is also given to one of them for the careful verification of the index. Of the book, therefore, it can merely be said that it completes the work projected a couple of years ago and the two volumes constitute a comprehensive and highly valuable presentation of the data on this interesting and important, and yet decidedly abstruse, field of physical HENRY LEFFMANN. chemistry. by a Special Committee of OVERHEAD SYSTEMS F&FEREKCE BOOK. Prepared the Overhead Systems Committee, Engineering National Section, National Electric Light Association. 592 pages, illustrations, quarto. New York, National Electric Light Association, 1927. Price, $7.50. This
comprehensive
work
on the
art
of
overhead
transmission
and
dis-
tribution of electricity has only recently appeared from the press. Although on Overhead Line Construction,” it is, in a way, a successor to the “ Handbook last printed in 1914 and out of print for some years, the new book has been The principal subjects, aside from tables completely rewritten and rearranged. and general information, are in order, Wood Poles, Steel Poles, Towers and Substation Structures, Materials, Insulators, Transformers, Protective Apparatus, Street Lighting, Electrical and Mechanical Calculations, Methods of Construction, Meteorological Data, Tree Trimming and general safety suggestions. All of these subjects are presented in such a manner that they are directly applicable to modern conditions and they have, therefore, a freshness and practical usefulness that is often lacking when old material has been reworked. Through selection of the most desirable methods that are employed in this important work in various sections of the country, it has been possible to present in tangible and readable form the most approved and satisfactory methods. Replete with illustrations, drawings and information, the work is the last word in present-day construction and maintenance. Appearing at this time, this text-book on overhead power lines assumes an added importance in view of the research work on power transportation
Dec., 19~7.1 started
BOOK
by the
methods
NELA
shown
investigating
NATIOKAL by Paul The
of
Pressure
as
year
a basis,
tests
Office,
described caused
to central
Aluminum error. Lengths
through
II pages,
E. Hemke.
Printing
the error
of aircraft
the last
in various the
Using
universities.
research
ADVISORY COMWITTEE FOK AERONAUTKS.
Measurement
mine
book
engineers
are
the
further
the subject with the view of possibly improving on the practices The work is well printed, on paper so far been selected as the best. manufactured for it, and is bound in full flexible fabrikoid.
that have especially
ment
during
in this
837
REVIEWS.
1927.
Tubes
illustrations,
Price,
quarto.
in this
report
were
made
small
tubes
to connect
capsules
No.
270,
Distribution Washington,
The
Tests, Govern-
ten cents.
by using pressure
Report
in Pressure
in making
by the
Committee
orifices
pressure
on the
distribution
to detersurface tests.
tubes of 3/r6-inch inside diameter were used to determine this from 20 feet to 226 feet and pressures whose maxima varied Single-pressure impulses for to 140 inches of water were used.
from 2 inches which the time of rise of pressure from zero to a maximum varied from 0.25 second to 3 seconds were investigated. The results show that the pressure recorded at the capsule on the far end of the tube lags behind the pressure at the orifice end and experiences also a change in magnitude. For the values used in these tests the time lag and pressure change vary principally with the time of rise of pressure from zero to a maximum and the tube length. Curves are constructed showing the time lag and pressure change. Empirical formulas are also given for computing the time lag. Analysis of pressure distribution tests made on airplanes in flight shows that the recorded pressures are slightly higher than the pressures at the orifice and that the time lag is negligible. The apparent increase in pressure is usually within the experimental error, but in the case of the modern pursuit type of airplane the pressure increase may be 3 per cent. For pressure distribution tests on airships the analysis shows that the time lag and pressure change may be neglected. Report No. 271, Pressure Distribution Tests on PW-g Wing Models Showing Effects of Biplane Interference, by A. J. Fairbanks. 13 pages, illustrations, quarto. Washington, Government Printing Office, 1927. Price, ten cents. In this report tests are described in which the distribution of pressures over models of the wings of the PW-9 airplane was investigated. The wing models were tested individually and in the biplane combination. The investigation was conducted in the atmospheric wind-tunnel of the Committee. It is concluded in this paper that the effect of biplane interference on the pressures on the wings is practically confined to the lower surface of the upper wing and the upper surface of the lower wing; that the overhanging portion of the . . upper wmg 1s not greatly affected by the presence of the lower wing; and that a slight washin at the centre section of the upper wing satisfactorily compensates for a reduced chord at this section (providing the air-foil section is not mutilated) and prevents a large reduction in the normal force over this portion of the wing.
[J. F. I.
REVIEWS.
presenting it in satisfactory form compelled the division of the work into two parts and has delayed the appearance of the second part. The same principles of arrangement followed in the first part have been In this present issue the reader will applied in the preparation of the second. find many examples paragraphs which References are also Almost everywhere secondary particles of colloid solutions the composition of
of the progress in knowledge on this subject and many are appendixes to the data given in the previous volume. made to data in the third and fourth editions of the work. one finds references to the significance of the primary and (monone and polyone) for the structure and characteristics and also the results of the exact investigation concerning the particles.
The preparation of the volume has been materially expedited by the services of collaborators whose work is gracefully acknowledged in the preface. Among these are Prof. Dr. Handovsky, of GGttingen, whose contributions are in the department of egg albumin colloids, and Doctor Thiessen, also of Gijttingen, who has contributed to the article on soap as well as certain other chapters. Several of the collaborators have been especially helpful in connection with proof-reading and credit is also given to one of them for the careful verification of the index. Of the book, therefore, it can merely be said that it completes the work projected a couple of years ago and the two volumes constitute a comprehensive and highly valuable presentation of the data on this interesting and important, and yet decidedly abstruse, field of physical HENRY LEFFMANN. chemistry. by a Special Committee of OVERHEAD SYSTEMS F&FEREKCE BOOK. Prepared the Overhead Systems Committee, Engineering National Section, National Electric Light Association. 592 pages, illustrations, quarto. New York, National Electric Light Association, 1927. Price, $7.50. This
comprehensive
work
on the
art
of
overhead
transmission
and
dis-
tribution of electricity has only recently appeared from the press. Although on Overhead Line Construction,” it is, in a way, a successor to the “ Handbook last printed in 1914 and out of print for some years, the new book has been The principal subjects, aside from tables completely rewritten and rearranged. and general information, are in order, Wood Poles, Steel Poles, Towers and Substation Structures, Materials, Insulators, Transformers, Protective Apparatus, Street Lighting, Electrical and Mechanical Calculations, Methods of Construction, Meteorological Data, Tree Trimming and general safety suggestions. All of these subjects are presented in such a manner that they are directly applicable to modern conditions and they have, therefore, a freshness and practical usefulness that is often lacking when old material has been reworked. Through selection of the most desirable methods that are employed in this important work in various sections of the country, it has been possible to present in tangible and readable form the most approved and satisfactory methods. Replete with illustrations, drawings and information, the work is the last word in present-day construction and maintenance. Appearing at this time, this text-book on overhead power lines assumes an added importance in view of the research work on power transportation
Dec., 19~7.1 started
BOOK
by the
methods
NELA
shown
investigating
NATIOKAL by Paul The
of
Pressure
as
year
a basis,
tests
Office,
described caused
to central
Aluminum error. Lengths
through
II pages,
E. Hemke.
Printing
the error
of aircraft
the last
in various the
Using
universities.
research
ADVISORY COMWITTEE FOK AERONAUTKS.
Measurement
mine
book
engineers
are
the
further
the subject with the view of possibly improving on the practices The work is well printed, on paper so far been selected as the best. manufactured for it, and is bound in full flexible fabrikoid.
that have especially
ment
during
in this
837
REVIEWS.
1927.
Tubes
illustrations,
Price,
quarto.
in this
report
were
made
small
tubes
to connect
capsules
No.
270,
Distribution Washington,
The
Tests, Govern-
ten cents.
by using pressure
Report
in Pressure
in making
by the
Committee
orifices
pressure
on the
distribution
to detersurface tests.
tubes of 3/r6-inch inside diameter were used to determine this from 20 feet to 226 feet and pressures whose maxima varied Single-pressure impulses for to 140 inches of water were used.
from 2 inches which the time of rise of pressure from zero to a maximum varied from 0.25 second to 3 seconds were investigated. The results show that the pressure recorded at the capsule on the far end of the tube lags behind the pressure at the orifice end and experiences also a change in magnitude. For the values used in these tests the time lag and pressure change vary principally with the time of rise of pressure from zero to a maximum and the tube length. Curves are constructed showing the time lag and pressure change. Empirical formulas are also given for computing the time lag. Analysis of pressure distribution tests made on airplanes in flight shows that the recorded pressures are slightly higher than the pressures at the orifice and that the time lag is negligible. The apparent increase in pressure is usually within the experimental error, but in the case of the modern pursuit type of airplane the pressure increase may be 3 per cent. For pressure distribution tests on airships the analysis shows that the time lag and pressure change may be neglected. Report No. 271, Pressure Distribution Tests on PW-g Wing Models Showing Effects of Biplane Interference, by A. J. Fairbanks. 13 pages, illustrations, quarto. Washington, Government Printing Office, 1927. Price, ten cents. In this report tests are described in which the distribution of pressures over models of the wings of the PW-9 airplane was investigated. The wing models were tested individually and in the biplane combination. The investigation was conducted in the atmospheric wind-tunnel of the Committee. It is concluded in this paper that the effect of biplane interference on the pressures on the wings is practically confined to the lower surface of the upper wing and the upper surface of the lower wing; that the overhanging portion of the . . upper wmg 1s not greatly affected by the presence of the lower wing; and that a slight washin at the centre section of the upper wing satisfactorily compensates for a reduced chord at this section (providing the air-foil section is not mutilated) and prevents a large reduction in the normal force over this portion of the wing.