GooDALL. — Geology of Timaru Downs. 457 



dolorite occur beds of fine browuisb-yellow material, interlaid 

 witb regular streaks of volcanic asli. Tbese beds curve witb tbe 

 bill, and do not occur in flat beds, as in marine deposits. The 

 regular streaks of volcanic asb are very evident in any new 

 cutting, and the pieces of asb can be readily picked out. Tbat 

 dolorite exists below tbe downs, and resting on tbe sbingle 

 plain, tbere is ample evidence, as both can be traced up all tbe 

 deep gullies ; and bas also been proved from wells tbat have 

 been sunk, from bores put down, and from quarries. The 

 shingle beneath the dolorite beds shows evidence of having been 

 subjected to great heat, and the dolorite in many places is scori- 

 aceous ; in fact, many pieces can be found that could not be 

 distinguished from Auckland (Mount Eden) scoria. Nobody can 

 for a moment doubt but that this dolorite was emitted as lava 

 from some volcano situated above these downs — probably near 

 Mount Horrible. This lava spread over the country in two or 

 three layers, pouring down in ridges. The volcano being spent 

 as to lava, it then, doubtless, belched out ooze and mud, with 

 occasional showers of cinders and ash. The ejected material 

 would overlay and envelope the dolorite beds. There is an 

 excellent section north of Timaru, formed by a railway cutting, 

 showing tbe dolorite bed, and above it the beds of ooze, with 

 mimistakable layers of cinders (PI. XXVIII.). In this bed of 

 ooze, deep down, I have found moa bones, but no trace of land 

 or marine shells ; and I have not observed the i^eculiar vertical 

 capillary texture observable in the true loess, as described by Dr. 

 von Haast. The occurrence of moa bones would tend to prove 

 tbat tbese beds were comparatively recently formed, as might 

 be from a sudden volcanic outbreak, and not from a slow forma- 

 tion as that of the loess, which would take ages, and so reach 

 the time prior to advent of the moa. 



I am led tbe more strongly to uphold the volcanic origin of 

 these downs from having seen very similar formations elsewhere, 

 when tbere could not be tbe slightest doubt of their formation. 

 Tbat was in Auckland, during the execution of the Auckland 

 improvement works at Albert Barracks. Heavy cuttings had 

 to be made for the streets, and one of these cuttings went 

 actually mto the cinder cone of an old crater. Further away 

 from tbe cone were similar beds to those at Timaru, with layers 

 of cinders through them.* 



There is a peculiar feature in these downs which is a puzzle 

 to all, and that is the occurrence of small lagoons or shallow 

 ponds on the brows of tbe hills. Almost invariably, as you 

 mount a hill you will find a lagoon on top. Had tbese lagoons 

 only occurred anywhere else, they would not have caused any 



* A drawing of this in section can be seen in the " Trans. N.Z. Inst.,'* 

 vol. vii., p. 144. 



