WELLINGTON NEWS

Hokitika Guardian, 6 September 1929, Page 2

WELLINGTON NEWS

THE CEMENT AGE. (Special Correspondent.) WELLINGTON, September 5. Professor C. H. Reilly, who has ocfcupied the Chair olf Agriculture at the University of Liverpool since 1904, considers that we are at the dawn of a new era so far as«building' construction is concerned, ferro-concrete being employed for all types of building work throughout the world? irrespective of climatic conditions.-..'The':,constant use of ferro-concrete has bad..the. result </ increasing the world; for cement "enormously. •,.In England mamcement works have had to;,'increase their output withfririecent, years. A typical instance is the Tunne’ Cement Works 1 on the Thames, near Tilbury, whose output. at the present time is approximately 250,000 tons per annum—double the output" qf four years ago. This is said to bp due largely to the increasing demand for British cement in Empire markets where uniform high-quality is essential. The Professor states that great strides have been made in recent years towards

improving the quality and hastening the hardening properties of Portland cement. Not many years-ago the British engineering standard specification

for Portland cement allowed a residue

of 14 per cent 'on a sieve of ! 82.400 meshes to the square inch. In 1925

this specification was revised and only 10 percent residue is now permissible on the same small sieve. Most British brands of cement are well within this limit. Tunnelite rapid hardening cement* for instance, shows a residue of only 1 per cent. It is the extreme fineness of this ; brand whifch

contributes very largely towards its rapid hardening qualities. Concrete made with tunnelite possesses the same strength -after two- days as ordinary

Portland cement concrete does after seven days. The quick-hardening enables building operations to be carried out expeditiously, and thereby costs are reduced. V- . ’' ; ''M* : It is distinctly encouraging to find that the 'cement, manufactured riiriNeiy •Zealand, is up to the . world -standfU’fij a- a matter of fact -in recent years New Zealand has progressed'similarly with England in regard to cement■ quality. Tli * Biitish standard specification ;is used as the standard- of ‘ guarantee in this Dominion, whereas in Australia '.a local specification ,which jnpludes {lie mechanical ramming of test pieces' force. ; . ‘ ! Tnere are three cement com pa lies opeiiiiing in New Zealand, two r n {ho af><jih Is’and -and one. in the North Bo’.b wfl fi.d dry systems are ui t.ie; th? latest machinery and methods ate adopted, .'and the - projects manufactured are very well thought of. The capacity of the existing., plants is. said ;n;>? greater than the demand. Portland rapid hardening Portland cement and hydraulic lime are the products manufactured and supplied, the latter being made continuously in rotary kilns, concurrently with the production of cement clink*r. Ordinary Portland cement of to dm has improved in quality enormously. Since 1927 all the cement made m New Zealand is of a qpality which at 24 hours is as hard as .that produced in 1919 was at seven days. Similarly The three-da} 7 hardness of-cement ma .iuf ictured from 1927 onwards is greater than the hardness in 28 days of the cement produced in 1919. Rapid-hard-ening Portland cements, intredu-e l locally some years ago, gives, strength

. and hardness in three days as great " and greater than present day Portland cements attain in 28 days. This type of cement has received favourable support for'speedy work,', and reinforced concrete piles have been successfully driven in 5 qnd 7 day's after mixing, on important ?' and large superstructures. Independent tests carried out overseas of New Zealand nrnde rapid hardening cement have demonstrated that it is equal to the best grades’ of similar hydraulic, cements manufactured in Europe and . America. BABY BEEF.

Throughout the whole of the world

there is at the moment an agricultural crisis, and the man who produces the

very fundamentals of existence is everywhere the least regarded and the worst remunerated. Agriculture is the foundation of human prosperity. Scientific research into agricultural problems is going on everywhere and the discoveries will lead to new and better methods of farming.

Recently a new agricultural research station was opened in Birkshire by Imperial Chemical Industqes. The station comprises two farms containing in all 436 acres, of which 160 acres is under the plough, the other consists of a grass holding of 76 acres. This latter has been set aside entirely for trials cn the production of baby beef. The research station is equipped with laboratories for analytical work, such as the examination of soil and fertilisers and for research into animal nutrition, biochemistry, etc.