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thermometer exposure is a very difficult one. What do we mean 

 by " temperature in shade ?" Is it the shade of a tree, a verandah, 

 or an iron shed ? A form of exposure known as the " Stevenson's 

 screen " has been adopted by the Royal Meteorological Society, and 

 is in extensive use elsewhere. Nearly, if not quite all, the Govern- 

 ment observing stations throughout Australia mount their ther- 

 mometers in this manner, and it is to be highly recommended. If 

 thermometers are not thus exposed a comparison cannot be made 

 with the statistics published by any of the recognised observatories. 

 The Stevenson screen is a wooden box i foot 6 inches high, i foot 

 8 inches wide, and i foot i inch deep, internal measurement. The 

 top and bottom are of double boards, having an air space of at least 

 an inch between, and plenty of ventilation, and the sides, including 

 the door, are of double louvres, so that the wind passes through, but 

 the direct radiation from the sun or ground is excluded. This is 

 mounted on four stout posts, with four others extending diagonally 

 from the top corners to act as supports in case of high winds. All 

 four thermometers, viz., dry bulb, wet bulb, maximum and minimum, 

 should be mounted in this screen, the two latter nearly horizontally, 

 and the two former vertically, but behind the others. If readings 

 can be taken only once a day, say at 9 a.m. the dry and wet should 

 be recorded first, so that the heat of the body will not vitiate their 

 reading. Then read the maximum and minimum without touching 

 them, but enter the reading of the former to the previous day. 

 After this has been done and checked, both of these maybe set, and 

 the muslin of the wet bulb be attended to if necessary. If obser- 

 vations are also taken at 3 p.m. it is better to read the minimum and 

 set the maximum at 9 a.m., and read the maximum and set the 

 minimum at 3 p.m. In this case, of course, the reading of the 

 maximum must be entered opposite the day on which it was taken. 

 The self -registering thermometers immediately after setting should 

 read the same, or nearly, as the dry bulb. 



RAIN GUAGE. This very useful instrument is so well known 

 that a description and instructions as to its use are hardly necessary. 

 It may be as well to state that the top scratch, or mark, on the 

 measuring glass registers 50 points, or half an inch, and that rainfall 

 observers in Western Australia are now instructed to record the 

 amount in " points." It may also be mentioned that the Perth 

 Observatory is prepared to issue rain guages to persons residing in 

 approved localities, and likely to settle permanently, upon the con- 

 dition that a record be faithfully kept and a monthly return be sent 

 to head-quarters on forms supplied for the purpose. 



WIND. The direction from which the wind blows should 

 always be noted, and it is desirable to have a vane erected in a well 

 exposed situation. A few hints as to the connection between the 

 wind and weather have already been given under the heading " The 

 barometer." It may also be added that the usual direction in which 

 the wind changes in the south-western and southern portions of thi s 



