414 

This is a work of thirty minutes. The bulletin of 
“probabilities,” which at present is all that is undertaken, 
is made out thrice daily, in the forenoon, afternoon, and 
after the midnight reports have been received, inspected, 
and studied out by the accomplished gentleman and able 
meteorologist who is at the head of this work. 
The “probabilities” of the weather for the ensuing 
day,so soon as written out by the professor, are imme- 
diately telegraphed to all newspapers in the country which 
are willing to publish them for the benefit of their readers. 
Copies of the telegrams of “probabilities” are also 
instantly sent to all boards of trade, chambers of commerce, 
merchants’ exchanges, scientific societies, &c., and to 
conspicuous places, especially sea-ports, all over the 
country. 
While the professor is preparing his bulletins from the 
reports just furnished him by telegraph, the sergeants are 
preparing maps which shall show by arrows and numbers 
exactly what was the meteorologic condition of the whole 
country when the last reports were sent in. These maps 
are printed in quantities, and give all the signal stations. 
A dozen copies are laid on the table with sheets of carbon 
paper between them, and arrow stamps strike in them 
(by the manifold process) the direction of the wind at each 
station. The other observations as to temperature, 
barometric pressure, &c., &c., are also in the same way | 
put on them. 
These maps are displayed at various conspicuous points 
in Washington—e.g., at the War Department, Capitol, 
Observatory, Smithsonian Institution, and office of the 
chief signal officer. They serve also as perfect records of 
the weather for the day and hour indicated on them, and 
are bound up in a book for future use. 
Every report and paper that reaches the Signal Office | 
is carefully preserved on file, so that at the end of each 
year the office possesses a complete history of the meteo- 
rology of every day in the year, or nearly 50,000 observa- 
tions, besides the countless and continuous records from 
all of its self-registering instruments. 
When important storms are moving, observers send 
extra telegrams, which are despatched, received, acted 
upon, filed, &c., precisely as are the tri-daily reports. One 
invaluable feature of the system as now organised by 
General Myer is that the phenomena of any particular 
storm are not studied some days or weeks after the occur- 
rence, but while the subject is fresh in mind. To the 
study of every such storm, and of all the “ probabilities” 
issued from the office, the chief signal officer gives his 
personal and unremitting attention. As the observations 
are made at so many stations, and forwarded every eight 
hours, or oftener, by special telegram from all quarters of 
the country, the movements and behaviour of every de- 
cided storm can be precisely noted; and the terrible 
meteor can be tracked and “raced down” in a very few 
hours or minutes. A beautiful instance of this occurred 
on the 22nd of February last, just after the great storm 
which had fallen upon San Francisco. While it was still 
revolving around that city, its probable arrival at Corinne, 
Utah, was telegraphed there, and also at Cheyenne. 
Thousands of miles from its roar, the officers at the Signal 
Office in Washington indicated its track, velocity, and 
force. In twenty-four hours, as they had forewarned 
Cheyenne and Omaha, it reached those cities. Chicago 
was warned twenty hours or more before it came. Its 
arrival there was with great violence, unroofing houses 
and causing much destruction. Its course was telegraphed 
to Cleveland and Buffalo, which, a day afterwards, it duly 
visited. The president of the Pacific Railroad has not 
more perfectly under his eye and control the train that 
left San Francisco to-day than General Myer had the 
storm just described. 
While the observers now in the field are perfecting 
themselves in their work, the chief signal officer is train- 
ing other sergeants at the camp of instruction (Fort 
NATURE 


[Sepz. 21, 1871 
Whipple, Virginia), who will go forth hereafter as valued 
auxiliaries. It has been fully demonstrated by the signal 
officer that the army of the United States is the best 
medium through which to conduct most efficiently and 
economically the operations of the Storm Signal Service. 
Through the army organisation the vast system of tele- 
graphy for meteorological purposes can be, and is now 
being, most successfully handled. ‘‘ Whatever else General 
Myer has not done,” says the Vew York World, “he has 
demonstrated that there can be, and now is, a perfect net- 
work of telegraphic communication extending over the 
whole country, working in perfect order, by the signal- 
men, and capable of furnishing almost instantaneous mes- 
sages from every point tothe central office at Washington. 
Think of a single jump by wire from San Francisco 2,700 
miles eastward three times a day! When General Myer 
undertook to put this system in working order, the tele- 
graph companies said it was impossible—no such thing 
had ever been heard of in telegraphing. It isnowa grand 
fait accompli, as much as the passing of the Suez Canal 
by ships or the escaping from Paris by balloons,” * 
At present the signal officer aims only to give a synopsis 
of each day’s weather, and a statement of what weather 
may be expected or will probably occur. The “ proba- 
bilities” so far have been most beautifully verified and 
confirmed, 
It is not thought wise to undertake more than can be 
securely accomplished. The synopses and “ probabi- 
lities” are all that intelligent shippers and careful seamen 
require. Shippers will not send their vessels to sea if the 
weather synopsis indicates threatening or alarming 
weather. 
Travellers can consult the “ probabilities” before leav- 
ing home; and any severe storm that menaces any city 
or port is now specially telegraphed thither, and the 
announcement is made by bulletins posted in the most 
public places. 
By the modest estimate of the signal officers, the fol- 
lowing is a table showing percentage of “ probabilities ” 
that have been verified : 
Fully verified . 
Verified in part 5 5 5 
Failed . : 0 5 - 25 
It must, however, be borne in mind that the failures 
have often been due to lack of information from points 
where as yet no observer-sergeant is stationed. 
FUTURE AIMS 
The Signal Service has, up to this time, acted upon the 
wise maxim of “ making haste slowly,” and undertaking 
to do nothing which was not in its power to do safely 
and securely without risk of failure. It has acted upon 
the confidence it has in the people that they will patiently 
await the development of solid science, meantime leaving 
no stone unturned to hasten forward the observations 
which may lead to a more exact acquaintance with the 
habits, movements, and tracks of our American storms. 
Great progress has in a very short time been made in this 
knowledge, and every day new light is dawning upon the 
science of storms. 
The instruments of the service have been bought on 
trial. They are undergoing the most varied experiments. 
In a short time, it is hoped, they will be greatly improved 
and perfected, and then the chief signal officer’s results 
will be more satisfactory to himself, and his labours will 
be greatly facilitated. The celerity with which important 
results have already been attained by this officer has sur- 
prised and startled both himself and the friends of the 
great movement. 
As soon as possible, therefore, the Signal Office will 
have its signal posts along the lakes and on our Atlantic 
sea-board, where cautionary signals will be displayed, 
warning vessels of approaching gales and storms, and 
* New York World, March 5, 1871. 
50 per cent, 
2S 
” 
” 
