SOLAR ECLIPSE, MAY 6, 1883. 



43 



wlien it rained steadily from about inidnigbt to 9.50 a. in.; it remained cloudy until afternoon, 

 when the sky gradually cleared. Following tlii.s day, the clouds were more frequent than they 

 had been for several preceding days, the wind stronger, the humidity .somewhat greater, and 

 showers more frequent. 



BAROMETRIC PRESSURE. 



The barometric pressure was markedly uniform from day to day, the diurnal movement being 

 clearly ajjparent. The following table contains the hourly barometric readings between April 25 

 and May C, reduced for temperature and elevation. Values in brackets are interpolated for the 

 purpose of obtainiug the mean values. 



Reduced barometric readings. 



It will be seen from this table that a barometric maximum occurred on each day at about 9 

 a. m., and a minimum at about 3 p. m. No regular barometric ob.servations wei'e made at uight 

 after 9 p. m., but Messrs. Preston and Brown, in conuectiou with their observations, read a mer- 

 curial barometer occasionally during the night. From these observations it is learned that a sec- 

 ond maximum occurred at about 9 p. m., and a secoiul minimum at about 3 a. m. 



The table also shows indications of a barometric period covering several days, a minimum 

 occurring April -9, and a maximum May 4. The latter was accompanied by the heavy rain-storm 

 elsewhere mentioned. 



AIR TEMPERATURE. 



The thermometric readings show a similarity from day to day, and also, as would be ex])ected 

 from an insular station, a small daily range averaging 9o.3. The highest reading noted was 89o.3 

 on April 28; the lowest 72°. 4 during the rain-storm on the morning of May 4. The minimum ther- 

 mometer placed on the ground gave readings nearly identical with those of the minimum thermom- 

 eter in the instrument shelter. 



The daily maximum temperature occurred at very nearly noon, and the minimum at about 6 

 a. m. 



HUMIDITY. 



The relative humidity was always great, ranging from an average of 70 per cent, in the middle 

 of the day to 84 per cent, in the early morning. The lowest value observed was CI ]>er cent, at 

 11.30 a. m.. May 2. 



