Evolution
to the Signal Service Years (1600
- 1891)
The Colonial Years
The
National Weather Service has its beginning in the early
history of the United States. Weather always has been
important to the citizenry of this country, and this was
especially true during the 17th and 18th
centuries. The early settlers to North America experienced
the harshness of the weather of the New World. Samuel
de Champlain, in the early 1600's told much about the
weather of the northeast United States when he stated:
"It
was difficult to know this country without having wintered
there; for on arriving in summer everything is very pleasant
on account of the woods, the beautiful landscapes, and
the fishing for the many kinds of fish found there. There
are six months of winter in that country. The cold was
severe and more extreme than in France, and lasted much
longer."
Samuel
de Champlain's sentiments were echoed in 1600 by Governor
William Bradford of Cape Cod who stated the winters to
be, "...Sharp and violent, and subject to cruel and fierce
storms, dangerous to travel to known places, and much
more to search an unknown coast."
Weather
also was important to many of the Founding Fathers. Colonial
leaders who formed the path to independence of our country
also were avid weather observers. Thomas Jefferson bought
his first thermometer while writing the Declaration of
Independence, and purchased his first barometer a few
days following the signing of the document. Incidentally,
he noted that the high temperature in Philadelphia, PA
on July 4, 1776 was 76 degrees. Jefferson made regular
observations at Monticello from 1772-78, and participated
in taking the first known simultaneous weather observations
in America. George Washington also took regular observations;
the last weather entry in his diary was made the day before
he died.
During
the early and mid 1800's, weather observation networks
began to grow and expand across the United States. Although
most basic meteorological instruments had existed for
over 100 years, it was the telegraph that was largely
responsible for the advancement of operational meteorology
during the 19th century. With the advent of
the telegraph, weather observations from distant points
could be "rapidly" collected, plotted and analyzed at
one location.
When
the telegraph became operational in 1845, the visionaries
saw the possibility of "forecasting" storms simply by
telegraphing ahead what was coming. Joseph Henry, Secretary
of the new Smithsonian Institution, envisioned opportunities
of the communication system and suggested that:
...a
system of observation which shall extend as far as possible
over the North American continent... The Citizens of the
United States are now scattered over every part of the
southern and western portions of North America, and the
extended lines of the telegraph will furnish a ready means
of warning the more northern and eastern observers to
be on the watch from the first appearance of an advancing
storm.
The
plan was approved in 1848, and subsequently, a circular
was distributed to the press to recruit volunteer observers.
Henry also persuaded the telegraph companies to allot
free time for the transmission of weather reports to the
Smithsonian.
By
the end of 1849, 150 volunteers throughout the United
States were reporting weather observations to the Smithsonian
regularly. By 1860, 500 of Henry's stations were furnishing
daily telegraphic weather reports to the Washington
Evening Star, and as Henry's network of volunteer
observers grew, other existing systems were gradually
absorbed, including several state weather services.
The
ability to observe and display simultaneously observed
weather data, through the use of the telegraph, quickly
led to initial efforts toward the next logical advancement,
the forecasting of weather. However, the ability to observe
and forecast weather over much of the country, required
considerable structure and organization--a government
agency.
Formation
and Evolution of The Division of Telegrams and Reports
for the Benefit of Commerce
The
catalyst for the formation of the new agency was Professor
Increase A. Lapham of Milwaukee, a student of meteorology.
Professor Lapham supported a storm warning service for
the Great Lakes and he sent frequent clippings of maritime
casualties to General Halbert E. Paine, Congressman for
Milwaukee. In one letter Lapham asked if it were not "...the
duty of the Government to see whether anything can be
done to prevent, at least, some portion of this sad loss
in the future...?"
Lapham's
enthusiasm for a national weather service was supported
by others, including the New York Chamber of Commerce.
One of the supporters was Colonel Albert J. Myer, Chief
of the Signal Service. Colonel Myer used a winter storm,
traced to Washington, D.C. from the Midwest, as an example
of the possibilities for such a weather service.
Congressman
Paine recognized the importance and practicability of
Lapham's cause and, on February 2, 1870, he introduced
a Joint Congressional Resolution requiring the Secretary
of War "to provide for taking meteorological observations
at the military stations in the interior of the continent
and at other points in the States and Territories...and
for giving notice on the northern (Great) lakes and on
the seacoast by magnetic telegraph and marine signals,
of the approach and force of storms."
The
Resolution was passed by Congress and signed into law
on February 9, 1870, by President Ulysses S. Grant. Little
attention was given by the press to the short, seven line
resolution, but an agency had been born which would affect
the daily lives of most of the citizens of the United
States through its forecasts and warnings.
Since
considerable structure and organization was necessary, and since
the operation of the new service was dependent on a reliable
communication system, the new service was placed under the Secretary
of War because "military discipline would probably secure the
greatest promptness, regularity, and accuracy in the required
observations." Within the Department of War, it was assigned
to the Signal Service Corps (which was organized in 1860) under
Brevet Brigadier General Albert J. Myer. General Myer gave the
National Weather Service its first name: The Division of Telegrams
and Reports for the Benefit of Commerce.
At
7:35 a.m. on November 1, 1870, the first systematized
and synchronous meteorological reports were taken by observer-sergeants
at 24 stations in the new agency. These observations,
which were transmitted by telegraph to the central office
in Washington, D.C., commenced the beginning of the new
division of the Signal Service.
The
weather service work of the new organization demanded
a large number of men familiar with observations, theoretic,
and practical meteorology. The commissioned officers detailed
to Signal Service work were required to acquire meteorological
knowledge by studying the available literature and consulting
with and receiving instruction from leading meteorologists.
For
the education of weather observers (enlisted men) a school
of meteorology was added to the existing school of instruction
in telegraphy and military signaling located at Fort Myer
(then Fort Whipple), in Virginia. Instruction for the
observers consisted of courses in military tactics, signaling,
telegraphy, telegraphic line construction, electricity,
meteorology, and practical work in meteorological observation.
In 1882, a course for commissioned officers was added
to the school covering meteorology, mathematics, and electricity.
The training school of meteorology at Fort Myer was abolished
by order of the Secretary of War in 1886.
Although
most of the weather observations were taken by the military,
the Signal Service turned to civilians for meteorological
knowledge. On November 8, 1870, General Myer requested
Professor Lapham to assume responsibility for the Great
Lakes region (with a salary of $167 per month), and Lapham
obliged by issuing the first storm warning the same day.
The dispatch sent to observers on the Great Lakes, read:
"High
wind all day yesterday at Cheyenne and Omaha; a very high
wind this morning at Omaha; barometer falling with high
winds at Chicago and Milwaukee today; barometer falling
and thermometer rising at Chicago, Detroit, Toledo, Cleveland,
Buffalo and Rochester; high winds probable along the Lakes."
In
1871, Professor Cleveland Abbe also became part of the
infant agency as Special Assistant to the Chief Signal
Officer. Following a month of practice, it was decided
that Abbe's forecasts, covering the next 24 hours, more
than filled popular expectations. The first public issuance
by Abbe was entitled "Weather Synopsis and Probabilities"
and was based on observations at 7:35 a.m. One of the
early examples is shown below:
Synopsis
for past twenty-four hours; the barometric pressure had
diminished in the southern and Gulf states this morning;
it has remained nearly stationary on the Lakes. A decided
diminution has appeared unannounced in Missouri accompanied
with a rapid rise in the thermometer which is felt as
far east as Cincinnati; the barometer in Missouri is about
four-tenths of an inch lower than on Erie and on the Gulf.
Fresh north and west winds are prevailing in the north;
southerly winds in the south. Probabilities; it is probable
that the low pressure in Missouri will make itself felt
decidedly tomorrow with northerly winds and clouds on
the lakes, and brisk southerly winds on the Gulf.
Since
the original congressional resolution covered only the
Gulf and Atlantic coasts, and the Great Lakes, the early
forecasts were made only for these areas. On June 10,
1872, an act of Congress extended the service throughout
the United States, "for the benefit of commerce and agriculture."
However, a sample forecast of 1872 reflects the lack of
data west of the Mississippi River.
"Partly
cloudy, but pleasant weather will prevail on Wednesday
for Pennsylvania and the upper lakes southward to the
Gulf. Cloudy weather will extend over New England and
Canada and clearing by Wednesday night."
Early
forecasts were made for eight large districts (which covered
the entire United States), three times daily and the duration
of the forecasts, as well as forecast elements were determined
by the forecaster. However, beginning in October 1872, predictions
were made regularly for 24 hours in advance for 9 districts,
and in 1874, forecasts were made for 11 districts and 4 elements,
namely weather, wind, pressure, and temperature. No changes
occurred until 1885 when predictions were made for 32 hours
in advance, and in 1886, forecasts were made for states, or
parts of states, as opposed to being issued for large districts
containing several states. In 1888, forecast durations were
extended to 36 hours and in 1898 extended to 48 hours.
Beginning
in 1873, forecasts were distributed to thousands of rural
post offices (by local Signal Service offices) for display
as "Farmers' Bulletins" in front of post office buildings.
This dissemination method continued until 1881 when local
signal flags replaced the bulletins. The flags were large
(for example, the cold-wave flag measured six-by-eight
feet and was white with a black center of two feet square),
and were displayed over post office buildings. By the
end of 1886, display flags were available at 290 cities
and towns.
The
Signal Service's field stations grew in number from 24
in 1870 to 284 in 1878. Three times a day (usually 7:35
a.m., 4:35 p.m., and 11:35 p.m.), each station telegraphed
an observation to Washington, D.C. These observations
consisted of:
- Barometric
pressure and its change since the last report.
- Temperature
and its 24-hour change.
- Relative
humidity.
- Wind
velocity.
- Pressure of the wind in pounds per square foot.
- Amount of clouds.
- State of the weather.
At Washington, D.C., forecasts were made from the telegraph
reports. The forecasts subsequently were distributed back
to the observers, to railroad stations and to available
news media.
Although
the forecasts did not always prove correct, they greatly
aided in planning daily life in the United States. A noted
scientist conveyed the increasing reliance on the weather
service when he declared: "While scientists cannot tell
at what hours to carry an umbrella, they can tell when
great storms and waves of intense heat or cold are coming
so as to be of great value to all the industries of the
land...All the discomforts of the weather cannot be avoided
but the great disasters can be anticipated and obviated."
Life
in the early field stations was not dull. Signal Service
personnel experienced a number of unexpected local events
(the suppression of labor riots in 1873) and isolated
Indian wars (including the Geronimo campaign). They also
performed extra public services during emergencies, including
yellow fever epidemics, plagues, and fires. In particular,
a detailed account of the Chicago fire is presented by
one of the weather observers in the Report of the Chief
Signal Officer, 1871-1872.
The
Report of the Chief Signal Officer in 1877-1878
described the duties of the enlisted men at the weather
offices:
...they
are required to take, put in cipher, and furnish, to be
telegraphed tri-daily on each day, at different fixed
times, the results of observations made at those times,
and embracing, in each case, the readings of the barometer,
the thermometer, the wind-velocity and direction, the
rain-gauge, the relative humidity, the character, quantity
and movement of upper and lower clouds, and the condition
of the weather. These observations are taken at such hours,
at the different stations, as to provide the three simultaneous
observations, taken daily at three fixed moments of physical
time (7:35 a.m., 4:35 p.m., and 11 p.m. Washington mean
time) throughout the whole extent of the territory of
the United States... Three other observations to be taken
at the local times, 7 a.m., 2 p.m., and 9 p.m., are also
taken and recorded at each station. A seventh and especial
observation is taken and recorded at noon on each day.
If at this observation such instrumental changes are noted
as to cause anxiety, the fact is to be telegraphed to
the central office at Washington.
An
eighth observation is required to be taken at the exact
hour of sunset at each location. This observation, embracing
the appearance of the western sky, the direction of
the wind, the amount of cloudiness, the readings of
the barometer, thermometer, and hydrometer, and amount
of rain-fall since last preceding report, is reported
with the midnight report...
The
average time elapsing from the time at which the readings
of the instruments have been had at the stations scattered
throughout the United States, to that at which the reports
based on these readings have been telegraphed to the
press and to the distributing-stations, has been one
hour and forty minutes.
Not
all reports from the Signal Service stations dealt with
weather observations. For example, the following memo
was concerned with another problem.
WAR
DEPARTMENT, OFFICE OF THE CHIEF
SIGNAL-OFFICER,
DIVISION OF TELEGRAPHS AND REPORTS FOR THE
BENEFIT OF COMMERCE AND AGRICULTURE
Washington, D.C., May 17, 1877.
SERGEANT: Should the Rocky Mountain locust appear at
or near your station at any time during the present
year, you will obtain all the information possible relative
to the following subjects, viz: The date of appearance
of the locusts; the direction from which they came;
the direction and velocity of wind and character of
weather at time of appearance; the length of time they
remain in your neighbor- hood, and amount of damage
done by them; the direction and velocity of flight;
direction of flight when they leave your station; whether
they fly with or against the wind; whether or not they
laid eggs in great quantities in the surrounding country;
what means were taken to destroy the eggs or the locusts;
any other information you can obtain on this subject.
Should the locusts have arrived at your station previous
to the receipt of this communication, you will obtain
all the information possible from the citizens residing
near you and forward it without delay to this office.
Make full notes in your daily journal in regard to locusts
and forward the same with the abstract.
Very respectfully,
Since
Signal Service forecasters and observers were in the Army,
rules and regulations were strict. Listed below are examples
of regulations in 1883:
Clerks
will keep their desks, their drawers, and file cases neat
and clean. Papers taken out of the files for action will
be returned as soon as the work in hand is completed,
and at the close of each day's work.
The
Property Officer will, each Saturday, have all rooms
halls, stairways, closets, cellars, etc., carefully
policed and arranged.
Drinking
vessels will not be used in taking medicine; nor will
the taking of medicine at water-coolers be permitted.
Discussions
in reference to the business of the office at any time
or place, not necessary to the proper discharge of the
duties of the same, are prohibited.
The
office rooms must neither be used as visiting rooms,
nor for purposes of entertainment. Persons visiting
the office are expected to transact their business as
promptly and briefly as practicable.
Unnecessary
conversations, writing of private letters, and reading
of newspapers during office hours are strictly prohibited.
Conversation necessary to the proper dispatch of business
will be carried on in a low tone of voice.
The
outfit of an inspecting officer will consist of one
standard mercurial barometer, two standard thermometers,
one standard compass, one jar of mercury; also the necessary
blanks, stationery, barometer cisterns, clamps and screws,
small screw drivers, and a tape-line.
He
(the inspector) will inspect the observer and assistants
in uniform, and examine them as to their knowledge of
the various circulars and orders issued by the central
office; and when they do not appear to understand any
one, or part of one, proper instruction will be given.
He will also examine them in the following text-books
of the service: Loomis' Meteorology, Myer's Manual of
Signals, Instructions to Observers, Pope's Telegraphy,
and Hand-book for the Signal Corps. The result of the
examination in each case will be reported under "general
remarks" in the inspection report. He will test them
in wand practice, and when there are facilities, in
telegraphy, giving the number of words received and
sent in each case.
All
maps and bulletins issued and posted at station will
be personally inspected, and their condition noted from
actual observation, and not from the observer's statement.
The date of the several maps and bulletins posted in
the frames at the time of inspection will be observed,
and if the latest issue is not found therein the observer
will be called to account for neglect of duty.
Military
authority is to be exercised with firmness, but with
kindness and justice to inferiors. Punishments shall
be strictly conformable to military law.
Superiors
of every grade are forbidden to injure those under them
by tyrannical or capricious conduct, or by abusive language.
During
the early years (1870's and 1880's) of the national weather
service, research studies were conducted at the central
office in Washington, D.C. The early research was comprised
mainly of topics dealing with the distribution of moisture
in the air, a treatise on the laws of meteorology, a report
on tornadoes from special observers in the Corps, and
instructional material for Signal Service trainees. Colonel
Myer, not overly interested in research, employed only
one permanent, civilian professor (Cleveland Abbe); but
Hazen added four senior and three junior professors after
1880. One man was in charge of investigations on atmospheric
electricity and another on thermometry exposure.
The
first 10 years under the Signal Service were tranquil
internally. General Myer, the chief of the new agency
from 1870 until his death in 1880, deserves much of the
credit. Myer possessed the ability to organize the agency
in a seemingly effective manner, resulting in minimal
internal strife. Myer stressed public service and the
personnel of the weather agency knew their job was service
to others.
Under
General Hazen, Myer's successor, the agency entered a
period of turmoil. From 1880 to 1887, the weather service
was rocked by allegations of fraud, scandals, and subsequent
investigations. In 1881, information surfaced that Captain
Henry W. Howgate (disbursing officer of the Signal Service)
had embezzled up to $237,000 from the U.S. Government
through the use of fraudulent vouchers. The Howgate scandal
resulted in a number of repercussions for both the weather
service and the Signal Service. Critics charged that employees
of the Signal Service aided Howgate, and Hazen was pressured
to reduce the expenditures of the Service by the amount
of the missing funds.
Also
under Hazen's administration, growing strife surfaced
regarding the degree of autonomy the Signal Service should
have as a component of the army. General Hazen maintained
that the Service should enjoy the status of a separate
corps, and therefore, more freedom in controlling its
own actions, as did the Army Engineers. Although the Signal
Service was able to maintain a certain degree of freedom,
it was becoming apparent that the Army was not happy with
the Signal Service in general, and the weather service
in particular. It also was becoming clear that the War
Department was not enthusiastic over having the weather
service. The Signal Service had been almost completely
absorbed by its new mission, and should its military services
ever be needed, its personnel could not be spared from
their weather duties.
In
1887, General Hazen died, and General A. W. Greely was
chosen as successor. The Greely administration failed
to quiet the storm of protest resulting from the previous
seven years of discord. Coupled with the increasing external
criticism was internal disharmony. One item surfaced when
Lieutenant John C. Walshe, inspector for the Signal Service,
told reporters that the man in charge of the predictions
at Washington, D.C., was too much a scientist and too
little a weather observer, preventing the transfer of
his theories into accurate forecasts.
By
1889, General Greely became convinced of the futility
of attempts to reconcile opposing factions within the
organization, as well as to correct admitted shortcomings
within the weather service. These admissions by the top
official of the military weather service solidified adverse
congressional reaction. Although Greely attempted to correct
the problems which had been building for over seven years,
the die was already cast and in 1889, President Benjamin
Harrison recommended transfer of the national weather
service to the Department of Agriculture. Congress agreed,
and on October 1, 1890, an act transferring the weather
service to the Department of Agriculture was signed into
law by President Benjamin Harrison.
According
to the new law:
...the
enlisted force of the Signal Service, excepting those
hereinafter provided for shall be honorably discharged
from the Army on June 30, 1891, and such portion of this
entire force, including civilian employees of the Weather
Bureau shall, if they so elect be transferred to the Department
of Agriculture...
The
work of the Signal Corps' meteorological division ended
20 years after it began; yet, in that brief period it
succeeded in establishing the foundation for the new Weather
Bureau. The United States already led the world in providing
public weather information, forecasts, and warnings. Charles
Patrick Daly, a famous jurist of the day, wrote:
"Nothing
in the nature of scientific investigation by the national
government has proved so acceptable to the people, or
has been productive in so short a time of such important
results, as the establishment of the Signal Service (weather)
bureau."
At the time of the transfer, General A. W. Greely wrote:
"In
parting from the civil employees the Chief Signal Officer
feels assured that the new chief in another department
will receive from them the same loyal, faithful, and efficient
service they have rendered the Government while serving
under his orders. The scientific staff have in view important
additional duties looking to the extension of the Weather
Service in the interests of agriculture and still further
development of the science of meteorology. The Chief Signal
Officer will follow with deep interest the development
of the new scientific field of weather forecasting and
the application of meteorology to agriculture, on which
grounds this liberal reorganization of the Weather Bureau
was planned and carried out."
So
on July 1, 1891, the weather stations, telegraph lines, apparatus,
and personnel (military people whom were honorably discharged
from the War Department and were now civilians) were transferred
from the Signal Corps' Division of Telegrams and Reports for
the Benefit of Commerce to the Department of Agriculture's new
civilian Weather Bureau.
Quarters of the Commanding Officer of Fort Whipple (Fort Myer),
Virginia (1876).
History of Fort Myer
From
1971 to 1886 most weather training for Signal Service
forecasters and observers was conducted at Fort Myer,
Virginia. In fact, Fort Myer was named for General James
Myer, the Army's first commander of the Signal Service.
Fort
Myer is located in Virginia just across the Patomac River
from Washington, D.C. Fort Myer originally was named Fort
Whipple and had its beginning in 1863. During the early
years of the Civil War, a federal defense committee recommended
that a series of military forts be built on the high terrain
of Virginia to protect the nation's capitol from the Confederate
Army. One of the forts constructed was Fort Whipple, named
to honor Brevet Major General Amiel Weeks Whipple, an
1841 graduate of the U.S. Military Academy.
Initially,
Fort Whipple was comprised of earthworks, tentage, and
temporary frame structures. By the late 1860s, the Signal
Corps had taken over the post since its location and elevation
made it ideal for visual communications.
General
Myer established the Signal Corps' headquarters, the Signal
Corps School, and the weather service school at Fort Myer.
The weather school for forecasters and observers was continued
at Fort Myer until 1887 when the fort was converted into
an Army cavalry fort.
The
first military test flights were made from the parade
field at Fort Myer on September 3, 1908. On that date,
Orville Wright succeeded in keeping his plane aloft for
1 minute and 11 seconds. Six days later, he made 57 complete
circles over the same field.
On
September 17, 1908, Orville was accompanied by an Army
Lieutenant on a flight over the parade field when a propeller
broke and the aircraft crashed. Wright was severly cut
and bruised, but the Lieutenant was killed, becoming the
first fatality associated with a powered aircraft.
Today,
Fort Myer remains in use by the Army. It is under the jurisdiction
of the commanding general, U.S. Army District of Washington,
D.C., but has its own post commander. It also is home of the
U.S. Army Information Systems Command which staff the Pentagon
Telecommunications Center, as well as other signal operations
in the National Capital Region.
Signal Service Office in Washington, D.C.
Because
of its location, the Washington, D.C. office was the central
forecast center for the entire country until 1887. The
first Signal Service weather office in Washington was
located in the building of the Chief Signal Officer. This
building was located on G Street near the War Department.
In 1871, this was the observers office. Upon the flat
roof of the building was erected a wooden observatory,
designed for the purpose of comparing thermometers and
other instruments. Also on the roof was one self-registering
rain gauge and one wind vane. All changes required at
other Signal Service offices, as well as all new instruments,
were thoroughly tested before being implemented.
Signal
Service Office in Washington, D.C., located on G Street
near the War Department. For over 17 years (1870-1887),
this building housed the headquarters of meteorological
operations for the Signal Service.
The first Signal Service weather office in Washington,
D.C. also served as the central office of the country.
Weather observations from across the country were compared
for errors. In addition, forecasters at the office prepared
maps and various weather bulletins, including forecasts,
for the eastern part of the United States. In 1871, Signal
Service forecasts and other weather information were posted
in the Signal Service office, the post office, and at
the main office of the Western Union Telegraphy Company.
Maps also were posted in the principal hotels in the nation's
capitol.
The
first Signal Service weather office contained a printing department
to print the maps and other weather information. In addition,
a separate department was available to evaluate the weather
instruments, and another for checking weather observations.
To support the various departments and functions of the office
was a correspondence and clerical staff.
NWS People During the Signal Service Years
The
early weather service had its share of characters. Since many
Signal Service weather offices were occupied by one individual,
personal discretion was important. Unfortunately, this was not
always the case. One observer in the Midwest who was addicted
to poker playing, frequently lost large amounts of money. The
observer went to a local pawnbroker and pawned the station's
instruments; consequently, the instruments were moved to the
pawnbroker's place of business. When the Signal Service inspector
arrived on station, he found no instruments. He found the instruments
in the pawnbroker's store and the observer taking the weather
observations in the pawn shop, instead of at the weather office.
Publications in the Signal Service
During
the 20 year history of the Division of Telegrams and Reports
for the Bureau of Commerce, considerable documents were
published for the benefit of the observers and forecasters.
As usual, the quality of the publications varied from
insightful (considering the level of science of the day)
to the ridiculous. Listed below are 12 publications, and
brief summaries, to depict the state of weather observing
and forecasting during the Signal Service from 1870 to
1890.
Memoir
on the Use of Homing Pigeons for Military Purposes
This
Signal Service Note describes the use of homing
pigeons by the military for carrying messages, including
weather information. A brief historical sketch of the
homing pigeon is presented, along with its various uses.
It was discovered that the practicability of using pigeons
to carry messages in time of war was not encouraging.
Despite great care in training, the pigeon frequently
failed during critical moments.
To
Foretell Frost by Determination of the Dew-Point
This
note describes the importance of measuring dew point temperature
for the purpose of forecasting the formation of dew or
frost. Tables are presented which relate wet-bulb and
dry bulb temperatures to dew point temperatures. It was
recognized that vegetation could be protected by "kindling
a small smudge fire." One interesting feature of the note
was that a complete hygrometer cost $7.00 and a minimum
thermometer $5.00.
The
Use of the Spectroscope in Meteorological Observations
During
the 1870's, Professor Piazzi Smyth, a Scottish astronomer,
suggested that the absorption lines in the solar spectrum,
might be used to forecast rain since the absorption spectra
varied with amount of atmospheric moisture. This study
presented results of a study to test Smyth's hypothesis.
The study found some correlation and it was suggested
that the spectroscope could represent a significant forecast
tool.
Weather
Proverbs
Since
the science of meteorology was relatively undeveloped during the
late 1800s, considerable emphasis was placed on heuristic rules
and folklore. This Signal Service Note listed many rules of thumb
and folklore which could be used by forecasters. The list was
compiled from Signal Service forecasters and observers across
the United States. Listed below are a selection of the weather
proverbs.
- A
red sun has water in his eye.
- When
the walls are more than unusually damp, rain is expected.
- Hark!
I hear the asses bray, We shall have some rain today.
- The
further the sight, the nearer the rain.
- Clear
moon, Frost soon.
- When
deer are in gray coat in October, expect a severe winter.
- Much
noise made by rats and mice indicates rain.
- Anvil-shaped
clouds are very likely to be followed by a gale of wind.
- If
rain falls during an east wind, it will continue a full day.
- A
light yellow sky at sunset presages wind. A pale yellow sky
at sunset presages rain.
Also
included in the document were rules of thumb for individual
Signal Service stations. Listed below are a few examples:
Albany,
NY
-
Storms set in with southerly winds, and are always preceded
by falling barometer, and usually by falling temperatures, with
nimbus or cumulo-stratus clouds.
Corsicana,
TX
-
Approach of norther indicated by bank of clouds in north or
northwest when the balance of sky is clear. Gentle or brisk
east wind precedes rain. Southwest or west wind indicates the
approach of clear, dry weather.
Indianola,
TX
-
"Northers" are preceded by protracted southeast winds,
rapid rise of barometer from four to six hours in advance
of storm, high humidity, with cirrus clouds moving from
the west.
North
Platte, NB
-
All storms approach from the northwest without reference to
direction in which wind may blow previously. Rain storms are
preceded by north or northeast wind.
San
Francisco, CA
-
Rain storms are preceded by falling barometer, low but
rising temperature, and west wind. During the rainy season
if wind veers to southeast rain follows.
Characteristics
of Tornadoes
-
The author of this Signal Service Note, John P. Finley,
described the results of his studies of tornadoes in the
United States. Considerable climatological information was
presented on tornado movement and times of occurrence. In
addition, general weather conditions prior to tornado formation
are described.
Finley
described tornado appearances, and provides preparedness
information on how to avoid tornadoes or to protect oneself
from related injuries. The note was detailed and provided
Signal Service forecasters with basic information on tornadoes.
The
Aurora in its Relation to Meteorology
-
During the Signal Service years, meteorologists speculated
on the importance of the Aurora to weather. The reasoning
was that the Aurora was the result of atmospheric electricity,
and like lightning, must occur with certain types of weather.
This Signal Service Note attempted to evaluate the potential
of Aurora occurrence to weather forecasting. Essentially
no correlation was found.