656 



Meteorological Apparatus. 



No. 55 465 



55465. 1:0. 



55 466. 1 : 5. 



55 467. 1 : 3. 



55 468. 1 : 7. 



55 469. 1 : 7. 



55.465. Direct Reading] Psychrometer after Lowe, giving relative humidity, dew-point, and 

 water vapour tension. Can be used without Table 



In order to make a reading, the index knob is moved up or down until the upper index gives 

 the same value on the temperature scale to the left as the dry-bulb thermometer to the right. The 

 index knob is then turned, without being moved, until the lower index gives the temperature-value 

 of the wet-bulb thermometer. The point at which the tip of the indicator is situated gives simultaneously 

 the relative humidity, dew-point, and the tension of water-vapour. 



55.466. Recording Psychrometer, Figure, with 7-day clockwork movement making one 

 rotation in this time, with two thermometers and two levers, writing on a drum . . 



55.467. Air Tester after Wolpert, Figure, for determining the amount of carbonic acid 

 in the air in rooms; specially recommended for schools. Accurate determinations in 

 a short time. With the necessary reagents in bottles 



s. d. 

 2. 10. 



55.468. Rain Gauge, Figure, 125 sq. cm surface, with cylindrical measure 



55.469. --idem, Figure, larger, 250 sq. cm surface 



V>.17<>. Rain Gauge after Bruhns, Figure, 500 sq. cm surface, with cylindrical measure 

 and 2 rods with branded marks (Ztschr. f. Instrk., 8, 1888, p. 208) 



55,471. Rain Gauge, ef. Fig. 55,472, consisting of graduated glass jar, brass cock, white 

 enamelled lead funnel and arbor screw, indicating to 10 mm rainfall 



55,471'. -- idem, larger, Figure, indicating up to 15 mm rainfall 



Cl. 6219, 1997, 

 1998, 1999, 



9. 0.0 



0. 12. 

 1 . 10. 

 2. 10. 



'2. M. ' 



0. 5.0 

 0. 6.0 



2000. 



