668 Transactions. — Chemistry and Physics. 



south as a line joining New Plymouth and Gisborne. The 

 isobar 29- 7 was recorded at Patea and Napier and 29-9 at 

 Westport and Castlepoint at 9 a.m. on that day. 



On the 24th the storm had progressed so far south that 

 the isobar 29-9 had reached the Bluff with east wind, and 

 the barometric reading was as low as 29-3 on the hne from 

 New Plymouth to Eussell, with wind from the north and east. 

 The centre of the disturbance was to the immediate west of 

 this line, and was probably about a hundred and fifty miles 

 wide from east to west and four hundred miles long from 

 north to south. The whole area of the storm within the 

 isobar 29-9 extended from New Caledonia, or a little to the 

 west of it, to about the same distance to the west of Chatham 

 Island, or nearly one thousand four hundred miles, and per- 

 haps nine hundred miles across in its widest part. 



On the 25th the centre of the storm, included within the 

 isobar 29-3, had reached the Ime Castle Point to Wanganui 

 with easterly wind, and thence round to Gisborne with wes- 

 terly wind. The eastern boundary of the central area was 

 probably two hundred miles eastward of Napier. The total 

 diameter of the storm within the isobar 29-9 was about one 

 thousand two hundred miles, and it was approximately circu- 

 lar,_ the original pear-shape having been modified by the 

 resistance met with in passing over New Zealand. 



But now an easterly moving antarctic storm is approach- 

 ing from the west, its centre being somewhere south-west of 

 Tasmania, and its eastern edge, with north wind, close to the 

 western edge of the tropical cyclone, with its south wind ; the 

 divide between the two circulations being about two hundred 

 miles to the west of Milford Sound. (See Plate LIII.) 



On the 26th the tropical storm has advanced to the south- 

 east so far that the south-eastern edge of the centre isobar 

 29 -3 has reached Chatham Island with its north-easterly 

 wind. The general shape of the outline of the storm has been 

 changed from the original pear-shape, with its long diameter 

 Iving north-west to south-east, into an oval, with its long 

 diameter lying north-east to south-west, and the north-west 

 isobar 29-6 about one to two hundred miles to the east 

 of New Zealand from the East Cape to Dunedin. In the 

 meantime the antarctic storm has advanced eastwards, and 

 has partially blended with the tropical storm, so that the 

 isobars 299, 29-8, 297 include both storms ; but there is a 

 divide between the antarctic isobar 29-6 with north-east wind 

 and the tropical isobar of 296 with south-west wind, a Httle 

 to the east of the east coast of the South Island. The advanc- 

 ing edge of isobar 29-3 of the antarctic storm has just reached 

 Milford Sound. Over the North Island lies a " high," with 

 anticyclonic circulation, included within the isobar 29-7, the 



