HiLGENDORF. — On Influence of the Earth's Rotation. 1209 



of the measurements T have visited, I think, ixll the chief streams 

 of Canterbury, with the exception of the Selwyn and Hinds. 

 Wlien I say " visited them," I mean I have travelled up and 

 down both their right and left banks from the mountains to the 

 sea, taking a section of the river under observation about every 

 four miles. The rivers and streams thus examined were th«'i 

 Ashley, Waimakariri, Rakaia, north and south branches of 

 the Ashburton, the Rangitata, Orari, Opihi, Otaio. Makikihi, 

 Waihao, and Waitaki. My outfit consisted of a bicycle, to 

 get from place to place, with a tested cyclometer to determine 

 the distances I had travelled up or down the river when taking 

 each section ; a pedometer, tested to record one mile for eacli 

 2,000 paces I walked, and which was very useful for determining 

 the width of terraces ; a chain tape measure and ball of string, 

 to determine the height of the most important terraces ; and, 

 finally, a couple of levels to find out when, standing on ojie 

 bank, I was at the same elevation as the top of the opposite 

 bank of the stream. One of these levels was a small dumpv, 

 and the other ;i small buildsr's level screwing into a stick, for 

 the rougher observations. My method of work was to choose 

 a road as near the banks of the river as possible, and every 

 four miles or so make expeditions on foot to the river-bank; 

 then, having found the first terrace, to walk to the stream, 

 recording the heights of the escarpments and the breadths of 

 the terraces as I went. This observation was supplemented at 

 a later date by a corresponding observation on the other side 

 of the river, at a point as nearl} as possible opjjosite the first. 

 Early in the course of the investigation I found that the con- 

 ditions obtaining on the plains were not as favourable as 1 had 

 imagined. The Rakaia and Rangitata do not flow down a 

 perfectly even slope, but my observations on these rivers are 

 included wath the others. On the other hand, it will be noticed 

 that no section of the Waimakariri is given, as it was evident 

 that the tw<^ disturbing factors mentioned — namely, want of 

 uniformity of texture of the plains and want of uniformity of 

 slope — are particularly obtrusive in this case. For the first 

 nine or ten miles of its course the river is continually held or 

 deflected by the fan of the Kowhai and Rock Ford ; by the 

 abutments of Eagle Hill, which run down into the river ; by the 

 Gorge Hdks, and by Brown's Rock. After a few more miles the 

 river, which used to ran through Prebbleton and down to the 

 sandhills at Halswell, is entirely thrown out of its course by 

 its own fan striking against the Port Hills, and its: present bank 

 is about nine miles from its old southernmost one. Owing to 

 the magnitude of the disturbing factors, then, the Waimakariri 

 was unsuitable for the purposes of the investigation. 



