6 4 



HARDWICKE'S SCIENCE-GOSSIP. 



reappearance at 6 hrs. 4 min. afternoon. On March 

 nth there will be an occupation yi Virginis, mag. 2^ ; 

 the disappearance takes place at 3 hrs. 7 min. in the 

 rning. 



Rising, Southing, and Setting of the Principal 

 Planets at intervals of Seven Days. 



Meteorology.— At the Royal Observatory, Green- 

 wich, the mean reading of the barometer for the week 

 ending 8th of January was 29.11 in. The mean 

 •temperature of the air was 31.9 deg., and 5.8 deg. 

 below the average in the corresponding weeks of the 

 20 years ending 1868. The general direction of the 

 wind was southerly, and the horizontal movement of 

 the air averaged 11.7 miles per hour, which was 1.5 

 below the average in the corresponding weeks of 16 

 years. Rain fell on each day of the week, to the 

 aggregate amount of 0.71 of an inch. 



For the week ending 15th of January, the mean 

 reading of the barometer was 29.87 in. The mean 

 temperature of the air was 33.1 and 5.0 below the 

 -average in the corresponding weeks of the 20 years 

 ending 1 868. The direction of the wind was variable, 

 -and the horizontal movement of the air averaged 9.6 

 miles per hour. Rain or melted snow was measured 

 on three days of the week, to the aggregate amount 

 of 0.19 of an inch. 



For the week ending 22nd of January, the mean 

 reading of the barometer was 30.07 in. The mean 

 temperature of the air was 37.1 deg. and 1.9 below 

 the average in the corresponding weeks of the 20 

 years ending 1S68. The general direction of the wind 

 was south-west, and the horizontal movement of the 

 air averaged 11.2 miles per hour, which was 2.6 

 below the average in the corresponding weeks of 16 

 years. Rain or melted snow was measured on three 



days of the week to the aggregate amount of 0.23 of 

 an inch. 



For the week ending 29th January, the mean 

 reading of the barometer was 30.179 in.; the mean 

 temperature of the air was 40.4 deg. and 0.5 above 

 the average in the corresponding weeks of the 20 

 years ending 1868. The general direction of the 

 wind was south-west, and the horizontal movement 

 of the air averaged 7.7 miles per hour, which was 6.3 

 below the average in the corresponding week of 16 

 years. No rain was measured during the week. 



For the week ending 5 th February, the mean 

 reading of the barometer was 29.96 in. ; the mean 

 temperature of the air was 44.2 deg., and 3.7 above 

 the average in the corresponding weeks of the 20 

 years ending 1868. The general direction of the 

 wind was south-west, and the horizontal movement 

 of the air averaged 16.1 miles per hour, which was 

 1.9 above the average in the corresponding weeks 

 of 16 years. Rain fell on three days of the week to 

 the aggregate amount of 0.29 of an inch. 



The mean temperature for March, is for Plymouth, 

 45°, Dorchester 44 , London 43 , Norwich, Sheffield, 

 Bradford and Lancaster, 42 . 



The average rainfall for March, which is generally 

 a very dry month, is from London to Berwick on the 

 East coast 1 inch, while from the Land's End to 

 Solway Firth along the West coast, it varies from 

 2 to 3 inches. 



RECENT ARTICLES AND PAMPHLETS 

 WORTH READING. 



PHOTO-MICROGRAPHY," by F. H. Evans 

 (" Photographic Journal," December 31). — 

 " Zoic Maxima, or Periods of Numerical Variations," 

 by L. P. Gratacap ("American Naturalist," Dec.) 

 ■ — "On Some Probable Causes of a Tendency to 

 Melanic Variation in Lepidoptera of High Latitudes," 

 by Lord Walsingham (" Transactions Yorkshire 

 Naturalists' Union," Part 8).— " The Sun's Heat," 

 Lecture by Sir William Thomson, reported in 

 "Nature," January 27. — "On the Morphology of 

 Birds," by Professor W. R. Parkeu" Nature,"Feb. 3). 

 —"The Rothamsted Experiments" ("Field," Feb. 

 1 2th). — "On some Carboniferous Cockroaches," by 

 Dr. Henry Woodward ("Geological Mag." Feb.) 

 — "Geological Visit to Brittany," by the Rev. E. 

 Hill ("Geological Mag." Feb.)— " Notes on the 

 Saffron Plant {Crocus saliva) and its connection 

 with the name of the town of Saffron Walden," by 

 Jcseph Clarke ("Essex Naturalist," Jan. 7).— "On 

 the Causes of Glacier Motion," by W. P. Marshall 

 ("Midland Naturalist," Feb.)— " Twenty-four New 

 Species of Rotifera," by P. H. Gosse ("Journal of 

 Royal Microscop. Soc." Feb.)—" On the Improve- 

 ments of the Microscope with the aid of new kinds 

 of Optical Glass," by Prof. E. Abbe ("Journal Royal 



