The subjoined map shows the curves of equal mean annual rainfall for every 10·0 inches for Australia, compiled from the most recent information:—
DISTRIBUTION OF THE RAINFALL OF THE COMMONWEALTH of AUSTRALIA
The following table shows the relative rainfalls at the six Australian capital cities for the periods set severally against them; also for the ten-year period subsequent to 1896, during which the average precipitation was much below that of the total number of years over which the records extend:—
| Place. | Total Number of Years. | Average Rainfall for all Years. | Ten Years' Average Rainfall. | Difference between the Two. | Difference for Ten Years. | Ten Years' Percentage per Annum above or below True Mean. |
| Inches. | Inches. | Inches. | Inches. | |||
| Brisbane | 57 | 47·47 | 39·16 | -8·31 | 83·10 | -18 |
| Sydney | 67 | 48·80 | 44·28 | -4·52 | 45·20 | -9 |
| Melbourne | 63 | 26·35 | 25·50 | -0·85 | 8·50 | -3 |
| Perth | 31 | 33·03 | 32·54 | -0·49 | 4·90 | -1 |
| Hobart | 66 | 23·38 | 22·98 | -0·40 | 4·00 | -2 |
| Adelaide | 67 | 20·89 | 20·53 | -0·36 | 3·60 | -2 |
The following table supplies similar information with respect to seventeen representative Queensland stations, from which it will be seen that the mean annual rainfall at Geraldton for twenty-one years was 145·27 inches, and for the ten years subsequent to 1896 135·81 inches. Thus Geraldton is by far the wettest place in the State. The lightest mean rainfall for the same period was at Boulia, which recorded 11·45 inches; and for the ten years, 8·72 inches. The last column of the table shows that the fall for the ten years was under the average at every station mentioned, the shortage at Cooktown having been 28 per cent. each year of the ten. The number of wet days is not supplied, except for the capital cities. The driest part of Australia—that which receives a rainfall of 10·0 inches and under—comprises an area equalling nearly one-third of the Commonwealth, and includes the central Territory of South Australia, the extreme western parts of New South Wales, the south-western parts of Queensland, and the south-eastern, central, and part of the north-western portions of Western Australia. The limits of this dry area are shown by the 10·0-inch isohyetal line:—
| Place. | Total Number of Years. | Average Rainfall for all Years. | Ten Years' Average Rainfall. | Difference between the Two. | Difference for Ten Years. | Ten Years' Percentage per Annum above or below True Mean. |
| Inches. | Inches. | Inches. | Inches. | |||
| Cooktown | 29 | 68·96 | 49·91 | -19·05 | 190·50 | -28 |
| Geraldton | 21 | 145·27 | 135·81 | -9·46 | 94·60 | -7 |
| Brisbane | 57 | 47·47 | 39·16 | -8·31 | 83·10 | -18 |
| Mackay | 36 | 69·42 | 61·73 | -7·69 | 76·90 | -11 |
| Maryborough | 36 | 46·58 | 39·49 | -7·09 | 70·90 | -15 |
| Goondiwindi | 28 | 29·27 | 22·99 | -6·28 | 62·80 | -21 |
| Tambo | 21 | 22·87 | 18·08 | -4·79 | 47·90 | -21 |
| Bowen | 36 | 40·40 | 35·62 | -4·78 | 47·80 | -12 |
| Blackall | 27 | 22·59 | 17·92 | -4·67 | 46·70 | -21 |
| Charleville | 34 | 19·71 | 15·30 | -4·41 | 44·10 | -22 |
| Hughenden | 22 | 19·12 | 14·92 | -4·20 | 42·00 | -22 |
| Thursday Island | 16 | 68·11 | 63·99 | -4·12 | 41·20 | -6 |
| Springsure | 30 | 26·25 | 22·54 | -3·71 | 37·10 | -14 |
| Boulia | 21 | 11·45 | 8·72 | -2·73 | 27·30 | -24 |
| Thargomindah | 25 | 12·53 | 10·03 | -2·50 | 25·00 | -20 |
| Cloncurry | 23 | 19·35 | 17·02 | -2·33 | 23·30 | -12 |
| Normanton | 35 | 37·11 | 35·26 | -1·85 | 18·50 | -5 |
The following table shows the distribution of the average rainfall from 10·0 inches and under to over 40·0 inches:—