THE

HURRICANE GUIDE:

BEING

AN ATTEMPT TO CONNECT THE

ROTATORY GALE OR REVOLVING STORM

WITH

ATMOSPHERIC WAVES.

INCLUDING INSTRUCTIONS FOR OBSERVING THE PHÆNOMENA OF THE WAVES AND STORMS;

WITH

PRACTICAL DIRECTIONS FOR AVOIDING THE CENTRES OF THE LATTER.

BY

WILLIAM RADCLIFF BIRT.

LONDON: JOHN MURRAY, ALBEMARLE STREET.
PUBLISHER TO THE ADMIRALTY.
1850.
PRINTED BY W. CLOWES AND SONS, STAMFORD STREET.

PREFACE.

In introducing the following pages to the notice of the Public, it is the Author's wish to exhibit in as clear a light as our present researches on the subjects treated of will allow, the connexion between one of the most terrific phænomena with which our globe is visited, and a phænomenon which, although but little known, appears to be intimately connected with revolving storms. How far he has succeeded, either in this particular object or in endeavouring to render the essential phænomena of storms familiar to the seaman, is left for the Public to determine. Should any advantage be found to result from the study of the Atmospheric Waves, as explained and recommended in this little work, or the seaman be induced by its perusal to attend more closely to the observations of those instruments that are calculated to warn him of his danger, an object will be attained strikingly illustrative of the Baconian aphorism, "Knowledge is Power."

Bethnal Green, April 19, 1849.

CONTENTS.

NOTICE.

In the pocket accompanying this work are two rings of stiff cardboard, on which will be found all the information contained in figures 1 and 2. When they are laid flatly upon a chart, the continuity of the lines on the chart is not materially interfered with, while the idea of a body of air rotating in the direction indicated by the arrows is conspicuously presented to the mind. These rings are more particularly referred to on page 52.

THE

HURRICANE GUIDE.

CHAPTER I.

PHÆNOMENA OF REVOLVING STORMS.

It is the object of the following pages to exhibit, so far as observation may enable us, and in as brief a manner as possible, the connexion, if any, that exists between those terrific meteorological phænomena known as "revolving storms," and those more extensive and occult but not less important phænomena, "atmospheric waves."

To the great body of our seamen, whether in her Majesty's or the mercantile service, the subject can present none other than the most interesting features. The laws that govern the transmission of large bodies of air from one part of the oceanic surface to another, either in a state of rapid rotation or presenting a more or less rectilineal direction, must at all times form an important matter of inquiry, and bear very materially on the successful prosecution of the occupation of the voyager.

In order to place the subjects above alluded to in such a point of view that the connexion between them may be readily seen, it will be important to notice the principal phænomena presented by each. Without going over the ground so well occupied by those able writers on the subject of storms—Redfield, Reid, Piddington, and Thom—it will be quite sufficient for our present purpose simply to notice the essential phænomena of revolving storms as manifested by the barometer and vane. The usual indications of a storm in connexion with these instruments are the falling of the barometer and the freshening of the wind, and it is generally considered that a rapid fall of the mercury in the hurricane regions invariably precedes the setting in of a storm.

There are three classes of phænomena that present themselves to an observer, according as he is situated on the line or axis of translation, or in either the right or left hand semicircle of the storm. These will be rendered very apparent by a little attention to the annexed engraving, fig. 1.

In this figure