400 METEOROLOGICAL REPORT, 1869, 



Wylam. — A cold dull month. 



Barometer— Mean height at 8 a.m., 29-900; highest, 30-889 

 on the 14th ; lowest, 29'123 on the 7th. 



Thermometer — Mean, 45-55°; mean of fourteen years, 50-93°; 

 deficiency of 1869, 5-38° ; highest, 62° on the 2nd ; lowest, 31^ 

 on the 9th. Mean of wet hulb, 43-64° ; of dry bulb, 46-29°. 



Rainfall — 3-86 inches ; greatest, 1-12 inches on the 7th ; days 

 of fall, sixteen. 



Height of river, 2-1 feet ; highest not observed. 



Wind— Resultant, E., 29° N. 



■Holly flowers in immense profusion. 



Whitley. — The month of May was cold throughout, and was 

 remarkable for tlie prevalence of northerly and easterly winds. 

 Vegetation was much checked. 



A very remarkable display of the aurora occun-ed on the 13th, 

 and seems to have been seen at very different points. The fol- 

 lowing account of an aurora, which was seen on April 2nd, is 

 from the pen of Mr. Plummer, of the Durham Observatory, and 

 was communicated by him to the Royal Astronomical Society of 

 London. 



"A short time ago the idea occurred to me that something 

 might be added to our knowledge of the nature of the Aui'ora 

 Borealis by means of the analysis of its light by the spectroscope, 

 and I resolved to examine its spectrum upon the first opportu- 

 nity. A very fine aurora was visible at Durham soon after mid- 

 night on April 2nd. It is the result of the observations made- 

 upon that occasion that I have now the honour to communicate 

 to the society. 



"The light of the aurora appeared to the eye as white, per- 

 haps slightly bluish, and not of the more common ruddy hue. 

 There were few or no rays, but broad sheets or waves of light 

 succeeded each other rapidly, proceeding from the arch to the 

 height of about 30° from the horizon, Upon being examined 

 by the spectroscope, one bright line was immediately seen. At 

 the brightest parts of the arch this line was perhaps equal in in- 

 tensity to that of the most conspicuous of the lines in the Nebula 



