VOYAGE FOR THE DISCOVERY OF SOUTHERN LANDS: 929
Thefe principles admitted it would not be extraordinary if the county of Cumber-land, comprized within the 35th degree of latitude fouth, fhould be expofed to con-fiderable inundations, did not the very nature of thefe inundations prefent the moftevident proof of their not being confequent on the rotation of the equatorial feafons.For in this rotation every thing is immutable, the rains and inundations have their dif-tin£t and appointed period ; they may be calculated upon and provided againft ; theyoccur but once in a year and never happen in oppofite feafons. While on the contrary,in what relates to the Hawkefbury River it has already been proved by experience,1 ft, that the overflowing of this Angular river takes place in all feafons of theyear ; '2d, that the recurrence of this circumftance varies from once or twice to eleventimes in a year, without any reafon aflignable for the difference ; 3d, that thefe pro-digious inundations have no relation whatever to the conftitution of the atmofphere asaftedted either by the violence or direction of the winds j 4th, that they are indeedoftentimes preceded by violent tempefts, but that thefe tempefts thetnfelves may devolvefrom any point of the horizon without their influence on the inundations appearingmore or lefs conftderabLe ; 5th, that not only have thefe inundations no general rela-tion to the feafon of the year or the nature of the winds, but they do not even preferveany order with refpecf to their recurrence : in fact, fix months have paft without anyflood happening, while again, three or even four times in a month has the river over-flowed its banks.
From all thefe faffs we may then deduce the remarkable confequence that the over-flowing of the rivers of New South Wales is not owing to the fame caufes as the inun-dations of equatorial countries, or even of thofe bordering on the tropics.
On the other hand, thefe phenomena are as little explained by what takes place intemperate climates, where the grand floods are chiefly occaftoned by the melting ofthe fnow, and in accumulated mountainous regions. The thaw in thefe is annual,and periodical; it commonly takes place in the fpring; at times, but very rarely doesthis happen, it is delayed until the dog-days : but when was it obferved in midft of thewinter’s cold ?
No other caufe therefore remains to which to aflign the overflowings of the Hawkef-bury River, but the frequency and abundance of the rain which falls on thefe mountainswhere it has its fource: but, allowing this, how wonderful muft thefe heavy rainsappear which can fuddenly occafion the waters of a fmall ftreamlet to rife to the heightof from 30 to 5Q feet, which happen at the moft oppofite feafons, occur fo frequentlyin a year, and in a manner fo independent of the conftitution of the atmofphere, of thecourfe of the winds, or of tempefts ! On what an immenfe extent of country muft theynot fall at the fame time! Flow rapid their courfe through the mountains, at once,and almoft inftantaneoufly, to unite in fuch prodigious mafles! It muft be allowed that,in this, as in many other phenomena, New Flolland defies our conclufions from com-parifons, mocks our ftudies, and Ihakes to their foundations the moft firmly eftablilhedand moft univerfally admitted of our fcientific opinions. As we proceed in fpeakingof this continent, juftly denominated by the Englifh the unequalled and wonderful,we fhall find ftill other and not lefs inconceivable examples of thefe apparently whim-fical freaks of nature : but before we revert to the fmall ftreamlets of Paramatta, whichinduced us to travel to the banks of the Hawkefbury, let us firft terminate what relatesto this Angular river.
If, by its inundations, it fpreads alarm among the cultivators fettled in its vicinage,what benefits, on the other hand, does it not diffufe over the country through which it
vol. xi. 6 c flows: