526 HENRY A. HUNT. 
storms and rains were not so general as on the thunderstorm — 
type, but curiously, were recorded in an almost parallel area of 
country, nearly three hundred miles wide by twelve hundred ‘ 
long. Though great barometric changes have taken place, the 
pressures remain about the same as on Chart No. 13. 
TYPE VII.—A RAIN STORM WITH VERTICAL AND NEARLY STRAIGHT 
ISOBARS. 
This type is one of the best defined and reliable of the series 
for forecasting purposes, because with them, good general rains 
almost invariably come. They are the rear isobars of a departing 
anticyclone, and the wind circulation from north and north-east 
brings into the interior winds laden with tropical moisture 
meet in the west southerly winds laden with antarctic cold, 
and therefore precipitating power. The sequence of rain is 
rendered even more certain if rain be recorded in the north-east 
before the isobars straighten, or in the , depression to the south. 
The actual height of the barometers is not material, but the 
greater the number of isobars in a given area, the more extensive 
will be the rainfall ; the rain usually lasts three days. The rail 
begins to fall north-west of New South Wales, spreads southwards, 
then eastward, and finally northwards, crossing the mountains 
near the Queensland boundary. A fine example of this type 
occurred on 15th, 16th, and 17th October, 1894. (Charts 16, 17-) 
On the 15th, Chart 16, a departing anticyclone rests on) 
Tasman Sea, and its rear isobars are shown revoning north and 
south over central Australia ; another anticyclo.ae is shown over 
Western Australia and a A depression east of the Australian 
Bight ; a trough of low pressure rests over Central Australia from 
ste to south. On this day the only indications of the pending 
rain were found in the cloudy skies generally over South Australia, 
western parts of New South Wales and Queensland, and a small 
area of rain in South Australia. 
‘In Chart 16, the straight isobars of Chart 15 have entirely 
disappeared, but the rain has come over Central and Soe 
