SAND LIME BRICKS.

Taranaki Herald, Volume LV, Issue 13947, 30 April 1909, Page 1

SAND LIME BRICKS.

MAM F \CTCHK» KKOM T )RA\\Kl IUAVW SAS»> AND TOKO U.\iK.

A samplo «f sand liino l)ii<ks. oC>iluiniiif.' N«'« I'lyniouth Mack sand, ■iMX"I v. itli a Mimil ijroporlion «i T»ko hinc 1-. imiw "ii oxln'liition us Mr^NowKiu Kind's pit uif*.s. l)<-wwi Siirot. ,\hnv ilu'V iiri- <»|»<*i* |>i>l)iif inspcrtioii. Tin- lui(ks conlnin r>« other 111L'ndiciHs Th<> miitorinls havmfe }>*-on ini\c(] to<i«.tln'r, slightly moisU'iu-ti And l>rcs,i'«l into shape under trciiU'iidoiw prisMirc, llu'.v wi'io piled on trucks •ikil to steam at a pressure of 1-20 (!>-. inw H(|iiar«' inch for a period it ien lio^us. An cxnmination of than >\ill no <loul)t satisfy as to their qunlily. It may he oi intere.st to know ,o'irn>tliiiiK of their ability to withstand "U'nther c«ii()itioiis. To do this it is neeoKMiry to K lV *' a I'ttlo information roßnrdinK tho origin of this class of 'niilfliiiH material. Sand bricks wore first manufactured in Europe, (icrmnnv bein^ the firtt to mtrofliKc them. Atterwards they were made m France and Rutland. Amoricn icok tlie matt<-r up some ei^ht or nine vi ins ayo nnd they are now used in ' .nin!<>n>« numbers ther<'. Over forty iv.-ais jiyu tho bricks were first used, hut were thfii moulded in the ordinary .rick moulds and were allowed to harl«n by exposure to tho atmosphere. Hv this method the bricks, after being noulded. had to He for many months h.-fore they were hard enough to handle Still, the atmosphere brought il.out the desired effect, namely, causing tho two ingredients to unite in fornunjj ft bond due to tho formation of, a hvdro-silieatc of lime. It was lm<M»Mble by thi" method to turn the •p.terpnso into a profitable one on iecount of the Wnuthot time the bricks had to lie in stock before being marketable. After many experiments it was lound that in the presence of moist heat the hardening process, became much accelerated. This moist heat •on Id" be obtained by steam from a boiler entering a closed vessel, into which the newly-moulded sand bricks had been placed. The results from this yore satisfactory. But at that t.me boilers ccttM not be built to withstand a high pressure, on<l consequently tho bricks had. to remain tinder »team a much longer timo than ul the CMC 1°; day. The brinks can now be hardened after being moulded iii ( nine to ten hours ready for laying in the *»H; The method of mannfartunng ibe bricks is a simple matter nowaday* with the greatly improved machinery. The brick is subjected to an enormous pressure in order to obtain the required density. It will readily be scon thiit with the improved conditions A better brick can be turned out in twenty-four hours to-day than equld be formerly in many months. Under, weather conditions the bricks continue 1 to Jiarden! and improve with age, not being affected either by frost or rain, other than b*lH>fl£iaHy. A» ercryon* »»«»«>,; the climate of Europe nnd North America is severe and extreme compareq with our New Zealand climate. Lime nnd sand aft ft Vnilding material can be seen to advantage lii Bnjdand and Scotland, where it has boon exp6sed to the- weather for many centuries. Often' where tho brick or stone has been eaten away tho lime joint can be seen to protrude and to be hard and tough. SarwJ bricks have been manufactured ■\t InFercargill for three years, and the 'ocal architects are satisfied as to the •ibility of these to harden with age. Over four millions have been built in md around Inveroargill since the factory started, bavins; been used by the Government in the construction of- a new f»aol. also for railway work, together with many Jcrge public buildings. The following are extracts from two Invercargill architects' letters: — Mr Charles Roberts, architect, writes as follows: — "Regarding your inquiry as to my opinion of your sand brick*, 1 think the fact, of which you are well aware, that f have used more of your sand bricks than any architect here is proof that I am well pleased with them. You are nware that I used the first lot of bricks which wore sent out of your works two and a hnlf years ago. I have used them continually ever nince, and am still using them. I find the bricks become harder with age. They are of good even size, shape and quality. They can be laid faster than clay bricks and require less mortar, which «r<nhles a bricklayer to make finer joints. I have studied sand brick manufacture for several years and consider they ure much preferable to clay bricks, where neat strong work is to bo considered, ttncklayers tell n?e they cost at least .'js per 1000 less to lay than the local clay brick. You may make what use you like of these remarks which might be of use to yon if you intend manufacturing elsewhere, ("•nee'ially ns 1 am not interested in any way with your brick company." Mr J. Rroderick, architect, Inver- 1 ci'mill, writes as follows: — "In reply ((v( (v \cnr inquiry re my opinion of the sand brick--! your company hns been making here during the last three years, I have pleasure in stating that1 ba\e used them largely in the erection of both public and private bnild-in<;-i here, with every satisfaction to myself and clients. Their principal, characteristic being regularity of shape, uniformity of size, rectangular faces, and freedom from flaws of any description, enables a very solid, substantial nnd uniform •• .• ".' to be built. With rei»nrd to t 1 " 1 durability of the brick, 1 have foi'- ' they are hardening with age os their composition suggested tlier would. I have every confidence in their future." A meeting will be duly announced v-hero a proposition will bo laid before the business men here by Mr Todd, who is here in connection with this matter, of starting a factory in or near Ni w Plymouth for the manufacture of these sand lime bricks.