MuLGAN.— r/ie Northern Wairoa. 459 



No. 2, about tivo miles and a half from Baiipo. 



Ft. 

 10 ft. clcxy or mud ... ... ... ... ... 10 



52 ft. soft sand and shell ... ... ... ... 62 



58ft. clay or mud ... ... ... ... ...-120 



12 ft. coarse sand. (Water rising near surface) ... 132 



18ft. clay (blue) ... ... ... ... ... 150 



8ft. sand, same as before ... ... ... ... 158 



18ft. soft sandy papa (blue), varies in thickness ... 176 



8 ft. hard pure papa. (Stopped sinking. Drew pipes 

 back to 120 ft. (see * above). Water rises 12 ft. above 

 ground, gives 3,000 gallons per twenty-four hours^ 

 clean water free from salt) ... ... ... 184 



No. 3, about three miles south of Baupo. 



10ft. soft clay ... ... ... ... ... la 



80 ft. dark quicksand ... ... ... ... 90 



6ft. hard clay ... ... ... ... ... 96 



17 ft. white sand (sharp) ... ... ... ... 118 



56ft. brown and blue clay ... ... ... ... 169 



41 ft. fine white sand, with flow at 2 ft. above surface — 

 good strong flow, gives 14,400 gallons per twenty-four 



hours clean and good water ... ... ... 210 



At Mangawhare the boring operations, which were carried 

 on with the same object as those at Eaupo, and which, more- 

 over, were not successful, in that the supply of water obtained 

 was insufficient, disclosed the following details : Beginning at 

 the surface, the pipes passed through 80 ft. soft wet river-mud,. 

 50 ft. fairly hard argillaceous limestone, 80 ft. calcareous marl 

 (papa). There were no traces of marine or fresh- water 

 organisms found in these (Mangawhare) deposits. 



The papa rock referred to both here and at Eaupo is an 

 indurated calcareous marl of presumably Cretaceo-tertiary 

 age, which outcrops at various places across this portion of 

 the peninsula. Taking this as the basement rock, we have 

 in the case of the Tokatoka Swamp a deposit of upwards of 

 200 ft. of sea-borne and river- borne sediment ; indeed, it is 

 highly probable that the depth of this deposit in places is not 

 far short of 300 ft., an immense depth when it is remembered 

 that it occurs in a relatively small land-locked harbour. The 

 material passed through in the borings, however, is not 

 altogether the product of the river. The eastern limit of the 

 sandstone series forming the land between the river and the 

 coast no doubt extended at one time as far as the flanks of the 

 hills to the east of the Kaipara Harbour. The upper members 

 have been removed by denudation, but the lower beds still 

 underlie the swamp-deposits. An examination of the tables 



