Analysis of certain Woods of Tasmania. 87 



In conclusion, I think that the result of the comparison 

 with the Koyal Observatory standard barometer warrants 

 me in recommending the Aneroid as a useful instrument 

 for all the ordinary purposes to which a barometer is 

 applied, or where scientific results are not required. As 

 a convenient and portable weather-glass it is valuable, 

 as it may alike lay on the drawing-room table, or be carried 

 in the coat-pocket without risk of injury; and its indi- 

 cations within the ordinary ranges of the atmos])heric 

 pressure on the earth's surface will be seen on reference 

 to the diagram to be most accurate. As a strictly scientific 

 instrument, to be employed in the mensuration of heights, 

 it is faulty, and, as far as I have been able to judge, from 

 the reasons already given : but it is well known how dijBfi- 

 cult a problem it has ever been, even with the mercurial 

 barometer, to make allowance for the expansion of air 

 and mercury with due exactness under all the varieties 

 of temperature and pressure to which an instrument is 

 subjected when employed in such investigations. 



VI. 



Account of the Analysis, hy'Dn, Motherwell, of certain 

 Woods of Tasmania, with a view to determine the 

 amount of Potash contained. By His Excellency Sir 

 William Thomas Denison, F.E.S., dec. dec. [Read 

 10th January, 1849.] 



In a number of the Farmer's Magazine, published, I think, 

 in 184G, there appeared an article on the cultivation of the 

 hop. The writer went very carefully into the subject, 

 giving an account of the various analyses he had made of 



