Bram.—On the Building Materials of Otago. 113 
In order to institute a comparison between the various articles under 
discussion, I give the following table of tensile strength per square inch in 
pounds on limes, cement, and mortar one year old. 
Cement and Limes neat. 
Portland cement... s em ... 500 pounds 
Roman i "ue a HAE a 
Good Modius Te e sks isa. ia 
DIDA n. pera de Pe UE p DRE R 
Rich lime  ... d RES is ses cdd a 
Mortars. 
Portland cement with 1 of sand ... ... 810 pounds 
j 5 cep. ree ere T a 
55 k E, ENER R a a AA ee 
- uc o an 100 ,, 
RN uc anc D n 
Ses diras lio mortar... s d EM iu. 
Ordinary 5 T Sm o MES A 
Good mortar of ihn ie. ses da T M 
Bad T F: Mic ide x uu ME ue 
Geographical Distribution. 
It was shown in a former paper that limestone as a geological formation 
occupies an immense area of Otago, but it does not follow that the supply 
of lime for industrial purposes is equally extensive, many of the calcareous 
rocks being incapable of producing lime of good quality. There is, however, 
no scarcity of lime suitable for building and agricultural purposes throughout 
the province. It is known to exist in considerable quantities in the follow- 
ing districts :—Oamaru, Otepopo, Waihemo, Maniototo Plains, Waikouaiti, 
Lower Harbour, Peninsula, Waihola, Waimea, Winton, Aparima, Waiau, 
and Wakatipu. These localities are so widely dispersed that we may safely 
calculate on a supply being available for any demand that can arise. 
The only natural cement hitherto discovered in Otago is the well-known 
Septaria or cement boulders of the Moeraki district, which resemble in every 
respect the English stones from which Roman cement was originally 
manufactured. According to Dr. Haast, the boulders follow the coast from 
Shag Point to the Terapupu Creek, then run in a straight line to the Little 
Kiwi Creek, which is struck at a point about half a mile from the sea. In 
the first four miles the deposit is a mere line of boulders lying on the beach 
or imbedded in the cliffs, but on leaving the coast it expands into a belt 
from 20 to 80 chains wide and 5} miles long. 
Many of the volcanic clays that exist in such profusion along the sea 
board from Saddle Hill to Oamaru possess cementitious properties similar 
o 
