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interesting operation was that of the removal of the arsenic from such 

 portions of the output of crude oil of vitriol as were to be converted 

 into pure sulphuric acid. This is effected by means of sulphuretted 

 hydrogen. There is no commercial use for the great masses of 

 yellow sulphide of arsenic which result. After an interval for lunch, 

 the party proceeded to the Tar Works, and saw the settling tanks 

 into which the tar is put as it is received from the gasworks. The 

 solid part, the pitch, is made into briquettes for fuel, the liquid 

 portion is distilled fractionally from large iron stills, the various 

 distillates yielding creosote, napthalene, anthracene, etc. The tar 

 as originally received contains a certain amount of gas liquor, and 

 this is worked up for ammonium sulphate, of which salt the firm 

 produces about 200 tons annually. Throughout the day the 

 weather was exceedingly inclement, but those members of the 

 Section who defied the rain and wind were rewarded by a most 

 instructive and interesting outing. 



Weather There was a good attendance of members of the 



Forecasts Section to hear the lecture delivered by F. I. 



Cooke, Esq., on Saturday, February 4th. The full 

 title of the lecture was " Weather Forecasts and the laws which 

 determine them." After a short introductory speech by the Chair- 

 man, Mr. Cooke explained the origin of the word " meteorology " 

 and the scope of the science, and then proceeded to the special 

 branch with which he had to deal. The following is a brief abstract 

 of his remarks :— 



The barometer is by far the most important of the instruments 

 used ; the imperfect and misleading wheel barometer is not, how- 

 ever, employed by scientific meteorologists. The direct readings 

 have to be corrected in various ways and the results are telegraphed 

 to the Central Office. The officials use these for the construction 

 of weather charts. Lines are drawn through places where the 

 barometer readings are equal and thus series of isobars are marked. 

 The chart thus constructed gives reliable information concerning 

 the direction and force of the wind in different parts of the area to 

 which it refers. Everywhere and always in this hemisphere if we 

 stand with our backs to the wind the barometer is lower to our left 

 hand than to our right. This is a statement of the law of Buys 

 Ballot, a generalisation of the highest importance. The diagrams 

 (shown on the screen by the lecturer) exhibited the different 

 arrangements of isobars and made clear what is meant by the 

 barometric gradient. The most important of the varities of isobaric 

 systems are the cyclone and the anti-cyclone. In the former the 

 gradient runs down toward the centre and in the latter it runs up 

 from the centre. In many respects these two are antitheses of each 

 other. Amongst other types of isobars connected with or derived 

 from the two principal kinds are the Secondary, the V depression, 

 the Wedge, the Col, and the straight isobars. 



From the chart with its isobars conclusions can be drawn as to 

 the direction and force of winds and also as to temperature, rainfall, 



