128 REPORT — 1855. 



which I have employed, consists in communicating the motion of the hemi- 

 spheres reduced by screw movements* to a vertical cylinder covered with a 

 plain sheet of paper ; a pair of pointed hammers strike a dot on each margin 

 of the paper on the completion of every hour; but when gales of wind or 

 storms occur, and the paper moves more rapidly, the spaces between the 

 hourly dots can be subdivided by throwing into gear another pair of hammers, 

 wherebvthe half-hours, quarter-hours, or even intervals of five minutes, may 

 be indicated if required. The pencil that traces the horizontal motion is con- 

 nectedwith the direction register, while thelinesthalindicatethe cardinalpoints 

 are at the same time ruled off by a series of narrow notched rollers. The di- 

 rection, horizontal motion,and time, are by these meanssimultaneously recorded. 

 The rain-funnel exposes an area of four hundred square inches, and the 

 water passes into a glass vessel below, suspended on a bent lever balance, to 

 which a pencil is attached, to record the quantity^ of rain that falls, on the 

 margin of the same paper as that on which the wind is registered. The line 

 traced will thus show the exact time at which each fall of rain commenced 

 and ended, while its curve indicates the rate at which it fell. To enable the 

 quantity of rain to be read with accuracy, the scale is enlarged, so that one 

 quarter of an inch of rain is represented by a space of two inches on the 

 paper ; whenever a quarter of an inch of rain has fallen, the glass vessel 

 discharges its contents, and the pencil returns to zero. 



The following Tables, prepared by Mr. Hartnup, are abstracts arranged 

 from the tabulated registers of the Anemometer and Rain-gauge at the Liver- 

 pool Observatory, during the years 1852, 1853, 1854, and 1855. The very 

 exact and punctual manner in which the records have been kept, as well as 

 the oreat amount of information tabulated, has given a peculiar value to 

 theni':— for the benefit of those who may take an interest in carrying on 

 similar observations, copies of tiie records for one month are printed in full, 

 showing how they are entered daily from the registers given by the instru- 

 ments. See Tables I. and II. . 



From the monthly sheets of which Tables I. and II. are specimens, the 

 annual Tables III. and IV. are obtained : in Table III. the results are 

 arrano-ed according to tlie points of the compass, and in Table IV. according 

 to the hours of the day. It is unnecessary to enter on a detailed description 

 of these, as the heading of each table and column affords sufficient explanation, 

 since found that this principle had been previously applied, tliough, I believe, not to registration 

 as reeards time Still, feeling the importance of obtaining the velocity as well as the force ot 

 the wind I som'e years afterwai-ds adopted the following method. A series of fans was fixed 

 on a li-'ht vertical wheel three feet in diameter, which was kept opposed to the current of the 

 airiuthedirectionof theaxis bymeans of thevane ; the fans were set obliquely at an angle which 

 decided the rate at which the wheel would revolve in proportion to the velocity of the air ; to 

 this I brieflv alluded in a paper which I brought before the British Association at Birmingham 

 fseeReuortfor 1849). The principle is exactly the same as Dr. Whewell's anemometer, the main 

 difference consisting in the fans being placed at a distance from the centre, and at so small an 

 anirle to the axis, as to reduce the motion to one-fourth or one-sixth, or any other proportion 

 of the velocitv of the air that might be required. Massey's Ship Log is also constructed on 

 thisDrinciple' For the purpose of keeping the fans steachly opposed to tlie current of the 

 air it is desirable to use awindmiU vane,as the continual oscillations of one of the ordinary kind 

 of vanes would seriouslv interfere x\ith the correct motion of the fans. This was just completed 

 wbpn the revolviuK hemispherical cups introduced by Dr. Robinson first became known to 

 me- the simplicity of this contrivance pleased me so much, that I at once decided on 

 annivinc it in preference to mv own, though I am inclined to think that in situations where 

 the instrument would be exposed to very violent storms, as in the tropics, the an-augement of 

 fans as iust described would probably be found-.of advantage, both on account of he small re- 

 sistance offeredinpassingthrough the air, and the slow rate at whichtheymay bemadetorevolve. 

 * In this instrimentffor every inch of paper worked off, the centres of the hemispherical 

 CUDS travel 12-75 miles, which, according to Dr. Robinson's experiments, is equivalent to ,58-^a 

 miles of air passing over the station : the results have been tabulated on this assumption. 



