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nutritive values, and this is very important, as there is no doubt
that cold-storage food will have to be used to a large extent.

By instituting a continuous chain of proper and effective cold-
storage and transportation facilities, which would insure the safe
delivery of foodstuffs with a minimum of deterioration and a minimum
of waste, some of the chief causes of the high cost of living would be
removed, and this balsa insulation system could be spread, not only
over the Western Continent, but all over the world. Foodstuffs would
travel from producer to consumer in balsa containers — parcel post
boxeSj pony refrigerators, automobiles, railroad cars, ships — to be
stored in balsa-walled storage warehouses, and, when delivered, would
be put away in balsa house refrigerators.

The scope of this enterprise is very great. Insurance and guaranties
would be furnished onsuch shipments, for witih such highly improved
methods to lessen the possible loss, insurance companies would find
it to their interest to establish a standard specification on which
basis the risk on perishable foodstuffs in transit could be covered.

The time is not far off when it will pay every architect to line
his buildings with 1 or 2 in. of balsa wood, not only as an insulation
lining but as a finish, instead of plaster and such coatings, which
crack and fall down. Very attractive effects can be obtained with
paneling in the interior of buildings.

There are a thousand and one uses for balsa, and in the future
new ones will continually develop. Thanks and grateful acknowledg-



160 DISCUSSION ON THE PROPERTIES OF BALSA WOOD

Mr. ment are due to Professor Carpenter for the earnest scientific work



Lundin.



he has done in investigating this wood.



Mr. Leonard M. Cox,* M. Am. Soc. C. E.— Although he can add nothing
of professional value to the discussion of this excellent paper, the
speaker feels a curious interest in the insulating properties of balsa
wood. Some 15 years ago, it was his fortune to serve as Chief of
Public Works at the Island of Guam, and among a number of more
or less serious problems which confronted the pioneers of that day,
was one which was never solved in an entirely satisfactory manner
with the materials available. The cold storage room of the miniature
ice plant served fairly well for caribou and American beef, but invari-
ably caused the loss of fully half the mutton and poultry begged from
the army transports on their monthly visits. From a first reading
of the paper, it seemed at least possible that a very common Guam
tree was akin to, if not identical with, the balsa tree, and that the
remedy for our cold storage troubles had been near at hand though
unrecognized. Personal notes consulted since the presentation of
the paper before the Society establish the fact that the Guam tree,
known locally as pago (Hibiscus tiliaceus), bears slight resemblance
to the balsa tree, except as regards its comparative lightness and
structure, as indicated by cut surfaces. Its weight per cubic foot is
24 lb.; it has considerable bending strength; is of about the color of
Flemish oak; and rarely grows to a size exceeding 6 in. in diameter.

The reference in the paper to the Marr wood-preserving process also
interests the speaker for the reason that while he was on duty at
the Norfolk Navy Yard in April, 1914, a number of experimental
timbers, running from 8 by 8 in. to 10 by 10 in., were impregnated
with the Marr paraffin, in which there was incorporated finely divided
silica. These pieces were suspended half in water and half in air,
beneath one of the Yard wharves. At the same time six pieces,
4 by 6 in. and 4 by 4 in., were impregnated with the paraffin without
silica, and buried to half their lengths in the ground. These test pieces
were examined on July 15th, 1915, and found to be in excellent con-
dition. They have also been examined during the latter part of June,
1916, and show no evidences of deterioration. The specimens which
had been placed in water had a small quantity of shells and vegetable
growth attached to their surfaces, all of which promptly fell off when
the timbers were struck. On cutting into the wood, it was found that
the interior was perfectly bright, and exhibited the distinctive red color
of the process. The pieces in the ground show no signs of rot or age.
Of course, tests on such a small scale cannot be considered deter-
minative, and it is hoped that other engineers will give the Profession
the benefit of any experience they may have had with this process.

• Brooklyn. N. Y.



AMERICAN SOCIETY OF CIVIL ENGINEEES

INSTITUTED 18 52



TRANSACTIONS



This Society is not responsible for any statement made or opinion expressed
in its publications.



Paper No. 1383

SUGGESTED CHANGES AND EXTENSION OF THE

UNITED STATES WEATHER BUREAU SERVICE

IN CALIFORNIA

Report of a Committee of the Southern California Association

OF Members.*

By George S. Binokley, M. Am. Soc. C. E.,
AND Charles H. Lee, Assoc. M. Am. Soc. C. E.



With Discussion by Messrs. N. C. Grover, William S. Post, Charles
T. Leeds, Fred. H. Tibbetts, J. B. Lippincott, and George S.
Binckley and Charles H. Lee.



The Committee, appointed by the President of the Association on
April 22d, 1914, to outline a plan for strengthening and extending
the mountain climatological work of the United States Weather
Bureau in California, so as to meet more widely and fully the needs
of the industries and communities of the State relative to water supply,
respectfully submits the following report.

Climatology is defined as that subdivision of meteorology which
treats of the physical 'condition of the atmosphere during an extended
period of time. Knowledge as to the climate of a place is obtained by
a study of its continuous weather records — atmospheric pressure, tem-
perature, rainfall, snowfall, direction and velocity of the wind, relative
humidity, and evaporation — for a long period of years. The general
relation of climatic factors to run-off and stream flow, as cause and
effect, is so obvious, even to the layman, that no discussion is necessary.

* This report was presented to tbe Southern California Association of Members,
Am. Soc. C. B., at its meeting of October 14th, 1914, and received the endorsement of
the Association.



162 WEATHEK BUEEAU SERVICE IN CALIFORNIA

Throughout much of California and the Southwest the important
streams have their sources in the mountain ranges bordering the val-
leys, and receive an almost negligible contribution from the valleys.
In many districts arid valleys lie adjacent to mountain ranges receiving
an annual precipitation of from 20 to 30 in. In such regions the
gathering of climatic data, as a basis for the study of stream flow
and water supply, should be carried on in mountains within the pro-
ductive portions of drainage areas. This fact has been generally
recognized throughout the West by irrigators, engineers, and some local
officers of the United States Weather Bureau, ever since the commence-
ment of irrigation development on a large scale.

The intimate relation which mountain precipitation, through
stream flow, bears to the development and settlement of California is
well shown by consideration of the communities and industries
depending on reliable water supply. Agriculture, the most important
industry of the State, to reach its greatest success, must generally be
accompanied by irrigation. This has been fully demonstrated in
Southern California and the San Joaquin Valley, and its truth is
now recognized in the central and northern part of the State. The
agriculturist, therefore, is fully as much interested in mountain
climatology as related to water supply as he is in the atmospheric
conditions immediately surrounding his crops. Hydro-electric power
is rapidly taking a leading place throughout the State in manufac-
turing, transportation, and agriculture, as well as in supplying the
physical needs of the inhabitants for light and heat. The reliability
of the supply is largely dependent on stream flow, so that here, again,
the average citizen is interested in mountain precipitation. Munic-
ipalities throughout the State depend for their very existence on
mountain stream flow, for, if they do not derive their water supply
directly from mountain run-off, as in the new Los Angeles Aqueduct
system and the proposed Hetch Hetchy development, their water is
pumped from underground reservoirs which, in turn, depend on pre-
cipitation and stream flow for replenishment. Finally, there is the
subject of flood control and prevention which affects more or less
the whole State and requires, to the fullest degree, deflnite and extended
knowledge of mountain climatic data for its correct solution. In con-
nection with this there is also the navigation of inland streams to be
considered in the Great Central Valley of the State. The many



WEATHER BUREAU SERVICE IN CALIFORNIA



163



interests which would benefit by the collection, co-ordination, and pub-
lication of climatic data from the mountains are thus apparent.

The practical usefulness of climatic data is in forming a basis
for the forecast of future stream flow variation. It is on the latter



MAP OF

CALIFORNIA

SHOWING THE LARGER STREAMS,
THE APPROXIMATE DISTRIBUTION
OF PRECIPITATION, AND THE
PRESENT AND SUGGESTED REGULAR
WEATHER BUREAU STATIONS.

Prepared to Accompany,

Report of Committee of Southern

California Association of Members of

the American Society of Ciril Engineers,

appointed to suggest changes
and extensions of U.S. Weather Bureau
Service in California.




Legend
• Regular Weather Bureau Stations
O Suggested " " "

^•—■Boundary drainage area
- 20- Line of equal precipitation






Fig. 1.



information that the magnitude or practicability of irrigation projects,
hydro-electric power systems, municipal water developments, flood-
protection works, or any other large engineering work, depending on



164 WEATHER BUREAU SERVICE IN CALIFORNIA

water supply or stream flow, is based. Such data have also great value
in the design of engineering structures for the control of water, such
as dams, spillways, head-works, bridges, levees, etc. There is still
another field that is beginning to be recognized, namely, in the business
management of projects depending wholly or in part on snow storage.
Where snow storage is the only source of supply, as is the case in many
irrigation and small power projects, a predetermined knowledge of
the season's supply would be of great value in making contracts for
the delivery of water or power. Where the snow storage is supple-
mented by other sources, a previous knowledge of the quantity available
makes possible a more complete economic planning for the develop-
ment of an auxiliary supply. The work of the United States Weather
Bureau in the Wasatch Mountains, Utah, has shown the practicability
of making snow surveys preceding the period of melting which are
sufficiently accurate to form the basis of contracts, between the irri-
gation companies and the irrigators, for the season's delivery of
water in the valleys.* Such data from the Sierra Nevada streams of
California would be of State-wide value.

It can be said, therefore, that comprehensive, accurate, and prop-
erly correlated data regarding mountain precipitation and related
climatic data, such as temperature, wind movement, barometric pres-
sure, humidity, and evaporation, are of the utmost importance in
the permanent and economically efficient development of the State.

The extent to which such data are made available by the United
States Weather Bureau in California will now be considered, first as
to the geographic and vertical distribution and then as to the character
of the observations.

The Bureau maintains stations of two classes: regular stations,
fully equipped with standard recording instruments, in charge of
trained observers; and co-operative stations, with incomplete instru-
mental equipment, observed without compensation, by public-spirited
citizens. There are 13 regular stations in California, of which C
are on the sea coast, 2 on the coastal plain, 4 in interior valleys, and
1 at Independence, Inyo County, at the western edge of the Great
Basin, in an arid region. There are no stations in mountainous regions,
or in fact in any region from which the local precipitation and run-off
will ever be an important source of water supply. There are listed in

* Engineering News, May 29th, 1913, p. 1110-



WEATHEK BUEEAU SERVICE IN CALIFORNIA 165

the California Section of the Climatological Service of the Weather
Bureau, Annual Summary for 1913, 192 co-operative stations, of which
17 (9%) are within 25 miles of the coast; 104 (54%) are in interior
valleys and foot-hills; 16 (8%) are in the Great Basin and desert;
and 55 (29%) are in regions of broken topography where the elevation
exceeds 2 000 ft. Of the latter, 4 are above 6 000 ft. elevation, 7 are
above 5 000 ft., and 21 are above 4 000 ft. The vertical limits of the
most copious mountain precipitation in California are between 4 000
and 6 000 ft. elevation. Of the 21 stations above 4 000 ft. elevation, 13
are in the Sierra Nevada Range, the remainder being well scattered
over the State. Of the 13 in the Sierra Nevada Mountains, 10 are
concentrated in the group of counties: Butte, Nevada, Placer, Plumas,
Sierra, and Alpine, which comprise only one-fifth of the length of
the range. The other 80% of this highly productive drainage area has
only 3 stations above 4 000 ft. elevation. The important area tribu-
tary to San Joaquin, Kings, Kaweah, Kern, and Owens Rivers has
only one station, namely at Bishop Creek, Inyo County, at an elevation
of 8 500 ft.

The character of the climatological observations made by the Bureau
will be considered : first, as to numerical climatic data obtained ; second,
as to location and exposure of instruments; and third, as to qualifi-
cations of observers.

The following data are obtained at regular stations:

(1) Continuous air temperature records;

(2) Wet and dry bulb thermometer observations for relative
humidity at 5 A. M. and 5 p. M.;

(3) Continuous precipitation records;

(4) Clearness of atmosphere;

(5) Continuous record of direction and velocity of wind;

(6) Continuous record of barometric pressure;

(7) Occasional water evaporation records;

(8) Miscellaneous observations.

Such data are all useful to the engineer as well as the climatologist,
and if obtained under representative local conditions are of great value.

At co-operative stations served by volunteer observers the following
data are obtained:

(1) Daily readings of maximum and minimum thermometers;



166 WEATHEK BDKEAU SERVICE IN CALIFORNIA

(2) Total precipitation each 24 hours as caught and observed iii
standard 8-in. gauges (snow catch usually computed as equiva-
lent water in ratio 10 to 1), depth of snowfall in 24 hours
measured on the ground, total depth of snow on ground
at time of observation;

(3) Miscellaneous phenomena, such as occurrence of frost, coronas,
thunderstorms, tornadoes, auroras, general phenomena of
climate, and general character of the day.

The method of snow measurement prescribed at co-operative sta-
tions is rather unsatisfactory, both in catching and in reducing to
equivalent water. Great improvement would result from the sub-
stitution of snow bins for the 8-in. rain gauges. It is a simple matter
to cut and weigh cores from the snow on a bin floor. Such a procedure
would eliminate the present elements of inaccuracy: first, as to the
effect on snow catch of wind currents about the mouth of the 8-in.
gauge; second, as to judgment of observer in ascertaining snow depth;
and third, in the use of the approximate ratios of fallen snow depth
to equivalent water.

The location of instruments at regular stations in large towns and
cities (9 out of 13 stations) is on the top of high office buildings. This
has a tendency to detract from the practical value of temperature, pre-
cipitation, and wind observations. As regards temperature, it is a
frequently observed fact in Southern California that on winter morn-
ings, when low growing crops are suffering from freezing temperatures,
the official record will show much milder temperature. This can be
explained, first, from the fact that the record is kept in an upper
and warmer air stratum, and second, by convection and radiation from
the steam-heated building on which the thermometer shelter is placed.
Then, as regards precipitation and wind, tall buildings cause vertical
and cross-currents and eddies, and these obviously affect the precipi-
tation catch as well as the anemometer record. At the regular stations
in small towns and at isolated points the location is usually on the
open ground, and far better exposures are secured. At co-operative
stations the thermometer shelter and rain gauge are usually on the
ground, but the gauge is often very poorly placed with respect to
obstructing objects such as trees, outbuildings, or houses.

The observers at regular stations are trained men who usually make
a life study of meteorology, and are accurate and systematic in their



WEATHER BUREAU SERVICE IN CALIFORiSriA 167

work. They are essentially indoor office men, however, and are not
encouraged by the Washington office to get out into the field, observe
conditions on the ground, and keep in close touch with local condi-
tions and the work of co-operative observers. There is no such body
of active, efficient, field observers, for instance, as is maintained by the
Water Resources Branch of the United States Geological Survey. As
a result of this policy, the Weather Bureau has in many respects failed
to meet the plain needs of western communities and provide data of
uniform reliability.

The co-operative observers are private citizens, without training
in systematic and accurate observation, who volunteer their services,
and receive no compensation. They place and observe rain gaxiges
without official supervision or instruction. Instruments are often not
understood, or are out of repair, readings are occasionally omitted, and
the general character of the observations is not by any means up to a
first-class standard. The obvious remedy for these defects is frequent
personal supervision by trained men from the district central office.
Nevertheless, the co-operative observers have filled a great need, and
the Weather Bureau is to be commended for its activity in finding
public-spirited citizens who are willing to undertake such work, and
for the rapidity with which these records are made available to the
public, and the convenient manner in which they are presented.

Summarizing the work of the Weather Bureau in California, as
regards the gathering of mountain climatic data, it appeaxs :

First. — That no regular stations are maintained within the produc-
tive drain nge area of any important stream of the State, nor are any
systematic scientific studies made of the subject;

Second. — That of the 55 co-operative stations maintained in moun-
tainous regions, 21 are, above 4 000 ft. elevation, of which only 13
are in the Sierra Nevada Range, and 10 of the 13 are concentrated
within about 20% of the area of the west slope;

Third. — That the co-operative stations are not equipped with instru-
ments or men capable of gathering intelligently the data necessary
for a comprehensive scientific study of mountain climatology as related
to stream flow;

Fourth. — That the Weather Bureau does not maintain a. corps of
trained field observers capable of supplementing and keeping in touch
with the co-operative observers;



168 WEATHER BUREAU SERVICE IN CALIFORNIA

7 Fifth. — That the placing of temperature, precipitation, and wind
recording instruments on high buildings is practically without value
to the agriculturist or engineer who attempts to use the data thus
obtained.

In great contrast with the lack of regular stations in the mountains
is their superabundance in the populated districts and along the coast.
For example, within 50 miles of San Francisco there are 5 regular
stations, San Francisco, San Jose, Point Reyes, Tamalpais, and Farallon.
In the Great Valley there are 3 regular stations. Red Bluff, Sacramento,
and Fresno ; and along the south coast there are also 3 regular stations,
San Luis Obispo, Los Angeles, and San Diego. At Independence,
in a desert region possessing the characteristics of the Great Basin,
there is maintained a fully equipped station which, because of its
location, can have no practical value in solving the water supply
problems of the State, unless supported by a station in the High
Sierra to the west. Hence, there is evident a great inequality and
inconsistency in the present distribution of regular Weather Bureau
stations.

The Committee, after careful consideration of the facts as just
stated and a study of the needs of the situation, presents the following
outline as a working basis for extending the usefulness of the Weather
Bureau :

I. — Establish at least 6 regular stations in the most productive
mountain drainage areas, fully equipped with self-recording instru-
ments and in charge of trained observers fitted for active outdoor field
work. These stations should be, not only points at which climatologic
data, are collected, but also the headquarters for field observers having
in charge local co-operative observers, and carrying on widely extended
climatic surveys and special studies. If lack of funds prohibits the
establishment of new stations, there is no reason why most of the
existing stations could not be moved. Such action would be rather
hard on certain of the Weather Bureau men, but would be of great
benefit to the people of the State as a whole, and tend to distribute
the benefits of the service more equitably. The locations of such
stations suggested by the Committee are as follows:

1. — In the drainage area of McCloud or Lower Pitt Rivers;
2. — In the drainage area of the Feather or Yuba Rivers;



WEATHER BUREAU SERVICE IN CALIFORXIA 169

3. — In the drainage area of Stanislaus or Tuolumne Elvers;

4. — In the drainage area of San Joaquin or Kings Rivers ;

5. — In the drainage area of Cache Creek above Clear Lake;

6. — In the drainage area of the Santa Ana River;

7. — In the drainage area of San Diego or San Luis Rey Rivers.

The conditions which should govern the location of these stations
are: accessibility by wagon road or railroad from populated districts;
accessibility in winter by skis or other means of travel for purposes
of reading snow gauges and making snow surveys at points several
days' journey distant; topographic features such as to insure the
representative character of the station records; they should be in the
zone of maximum rather than minimum precipitation for the drainage
area; and, generally, should be where the facilities for the study of
climatology as related to local water supply would be the best.

IT. — Increase the number of co-operative stations in mountain areas
now sparsely covered or not covered at all. In uninhabited areas,
where neither mining settlements nor forest ranger stations are avail-
able, establish rain and snow gauges capable of holding a catch for
an extended period.

III. — Organize a corps of trained field observers whose duties it
will be to supervise personally the work of co-operative observers, and
make special field studies, such as listed under IV.

IV.— Make special studies as follows, in as wide a territory as
possible :

1. — Annual snow surveys in the drainage areas of Sierra Nevada

streams ;
2. — Snow movement subsequent to precipitation;
3. — The relation ,of temperature, forest trees, drifting, etc., to

snow melting;
4. — The detailed relation between topography and precipitation;
5. — Water evaporation from lakes or reservoirs;
6. — Evaporation from snow;
7. — Establish, maintain, and observe snow and rain gauges at

isolated points which can be reached only at long intervals;
8. — Any other investigations of practical value in the solution of

the water-supply and flood-protection problems of the State.



1?0 WEATHER BUREAU SERVICE IN CALIFORNIA

The Committee has been frank in its criticism of the apparent
fact that the principal meteorological observatories have generally
been located rather more with reference to the comforts of a city than
to secure the greatest efficiency and collect the most valuable data. This
criticism, however, is not unfriendly. The staff of the Weather Bureau



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