Page 3 Advertisements Column 3

Dominion, Volume 15, Issue 242, 8 July 1922, Page 3

TENDERS. SALE OF STORAGE SHEDS. FOR SALE, by Tender, Five Sheds recently used for storage of building materials for Workers’ Dwellings. The Storeman. Labour Department, Timher Yard, Miramar, will show the Sheds to intending purchasers. Tenders close at 9 a.m. on Monday, July 17, and are to be sent in sealed envelopes, endorsed "Tender for Miramar Storage Sheds, and .addressed to "The Housing ®uperintendent, Department of Labour. Ihe highest or any tender not necessarily ac- ' r. w. zowiar. Secretary for Labour. FRANKTON JUNCTION. TIMBER-DRYING KILNS. XXTR.ITTEN TENDERS will be reV v ceivtd at the office of the General' Manager, Railways, Wellington, up till Noon on' TUESBAY, JULY 25. Particulars available at the offices of the Stationmaster, Auckland. Inspector of Building Construction, Frankton. Junction, and Architectural Branch. Bunny Street, Wellington. The lowest or any tender not necessarily accepted. TO ARCHITECTS. BUILDERS. AND OTHERS IT MAY CONCERN. '■- I ■ • HUTT RIVER SHINGLE COMPANY. IS it good business to purchase and use inferior materials when by a slight increase in cost materials can be obtained that will give an increase m strength of at least 25 per cent. P You gain either by an increase in strength for the same weight, or obtain the required strength of structure by the use of leas material. In the latter case the cost would be approximately the tame as when the inferior materials are used .owing to four causes: — a. Less material to purchase. b. Less material to cart. c. Less material to work into place; d. The size of the foundation and other parts will be reduced owing tb there being less weight to carry. But a structure of more certain strength is obtained. The above-mentioned pointe must all be considered in building construction, and the increase in strength for the same weight is bv no moans of small importance when the life of the building is taken into account, especially in an earthquake country. Have you ever considered the effect of eilt in your\ concrete materials? Experience and' experiments have shown that silt, mud. or similar substances have a deleterious effect upon the setting. as well as upon the strength of the concrete, with a resulting decrease in its strength. It ia not known exactly why this is so, but when you consider the enormous proportion of surface area to volume of the fine particles ( of the silt and that the whole of thia surface has to be covered with the cement, the fact ■ impresses Itself on one of how impossible it is for a limited quantity of cement to do this, especially as particles of cement before setting are approximately the same size as the particles of silt. To obtain the best results, first-class practico in concrete contraction calls for eand composed of sharp, 1 hard, and gritty grains, and not more than 10 per cent, should pass a sieve having 2500 meshes per square inch, that is. particles l-64t1) of an inch and smaller in size. . / Just recently tests have been made at the Canterbury University and also by a well-known Corporate Body in Wellington, and th 4 average results of tjiese teste give a breaking strength for unwashed Hutt River Shingle of 22401 b per square inch. For Hutt River Shingle Company’s Stone crushed, washed and graded and wash sand a breaking strength of 29001 b. per square inch. This shows an increase in strength of. over 25 per cent, in favour of crushed stone and clean material. This increase in strength is due to two causes—the use of clean material and the use of crushed stone. On water-worn stone the surface has been worn smooth and’the bond between the cement and the stone i» by adhesion only. Ths surface of* a fracture varies with each class of rook, but generally it is rough with little indentations. The cement In this case has a greater surface to adhere to owing to the roughness, and it, also obtains a bond in the indentations. , Therefore, concrete made with broken stone must be stronger than when smooth stones are used. No one can afford to risk endangering the safety of any building by the use of inferior materials, as the strength of a column or beryn depends upon the strength of the weakest batch of concrete used. Nobody can foretell the strength of concrete made with dirty materials, nor when the materials aro not mixed in their proper proportions, that is to say, the dimensions of tho particles of sand and stone must bear a proper relative proportion to the mass. It is impossible to obtain this result by the haphazard methods generally in use at the present time. The best results can only be obtained by separating the stones and sand by screening, and then measuring thorn in their proper proportions in small batches at the time of mixing the conAll high-class specifications the world over now call for absolutely clean and properly graded concrete materials so as to ensure as near as is humanly possible that the resulting concrete shall be even in quality and strength throughout the structure. ■ Can you'afford to depart from "Wit practice has shown to be absolutely necessary through repeated failures. By the foregoing we have endeavoured to point out the advantages of the use of the best and cleanest materials in concrete construction, and we will have much pleasure in referring interested parties to the results of further tests that are available. CARTAGE * CUSTOMS SERVICES. MUNT COTTRELL AND CO.. LTD., Carriere and Forwarding Agent*. Coach and Motor Body Builders. Motor-oars Upholstered, Painted, and Enamelled (W. Cummins. Foreman Painter). / We have plant and facilities for hand1 ling everything. Agents for Yorkshire Insurance Co., Ltd,' Adams and blyth, ltd.. DAMS AND BLYTH; LTD., CARTAGE CONTRACTORS, SHIPPING AND FORWARDING AGENTS. Customs Clearance a Specialty. 130 Featherston Street, Wellington. CLIENTS guaranteed quick delivery, together with prompt return of INVOICES AND ACCOUNT FOR CHARGES. P.O. Box 1896. 'Phone 1270. Telephone 2790. P.O. Box 800. PARBTHNB AND CO.. VaRSTENS AND 00., Customs, Shipping, Forwarding, and General Agents, HARRIS STREET, WELLINGTON. Agencies throughout New Zealand. "T F. TOSSWILL; Carrier, Lowct XX* Hutt-Wellington, daily. Storage Office, Scott's Lane, off Dixon Street. 'Phones :City 22—268; Hutt, 23 (8 rings). ' yCIRdTRICTION" Carburettors fit any -M oar. and give more power with 30 to »O per cent, less fuol. Much easier starting In cold weather, and no choking in shifting gears. Manning Machinery Co.. 5 Bedford Row. Christchtiroh.