Scientific Intelligetice, — Meteorology, 18S 



other, till they almost appear to unite, or the space between them 

 is upon a line placed at a right angle to the primitive line which 

 united them. 



The isotiiermal lines, consequently, are composed like the iso- 

 chromatic curves of certain crystals, when their temperature is gra- 

 dually raised. At the same time, the observations of high lati- 

 tudes are as yet too general to enable us to decide definitively on 

 this question. 



At certain epochs of the year, accordingly, the earth has only one 

 cold pole. The isothermal lines of the mean zone turn so much in 

 their progress, that in some countries they become perpendicular 

 during half the year, in relation to the direction they maintained 

 during the other half. We are unacquainted with any parts of the 

 earth, whose temperature does not fall, during some of its month?, 

 below the freezing point ; and there are places whose temperature 

 is so low, that the mean of a whole month descends below the point 

 which freezes mercury. — E Institute 8 an. No. 323, p. 106. 



4. Mirage in New Holland, — There was one other district exa- 

 mined by us, which possesses such peculiar characteristics, that 

 even in this short report I am induced to call your Lordship's at- 

 tention to it. I have named this the district of Koo-heni-triet, 

 that is, the district of Falsehood or Deceit. It is situated between 

 a point lying about ten miles to the north of the northern mouth 

 of the Gascoigne and Cape Cuvien The whole extent of its sea- 

 coast is bounded by a range of lofty sandy dunes, having a width 

 inland of not more than from two to two and a half miles. The 

 first time that I ascended this range, was on the morning of the 

 8th of March 1839, at a point about fifteen miles south of Cape 

 Cuvier. On looking to the eastward, I was surprised to see an ap- 

 parently boundless expanse of water in that direction. I hurried 

 back to the boats, and selected three men to accompany me in my 

 first examination of the shores of this inland sea. When we gained 

 the top of the sandhills, the surprise of the party was as great as 

 my own, and they begged me to allow them to return, and endea- 

 vour, by the united efl^orts of the party to carry one of the whale- 

 boats over the range, and at once launch it on this body of water. 

 I, however, deemed it more prudent, in the first instance, to select 

 the best route along which to move the whale boat, as well as to 

 choose a spot which aff^orded facilities for launching it. In pursu- 

 ance of this determination, we decended the eastern side of the 

 sandhills, which abruptly fell in that direction, with a slope, cer- 

 tainly not much exceeding an angle of 45°. I now found that the 

 water did not approach so near to the foot of the hills as I had at first 



