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Building and Bushwork for
Selectors, Squatters, and others.
WRITTEN FOB THE TOWN AND COUNTRY JOURNAL
BT 3?RED. HARBISON, M.V.l.A., DENILIQUIN.
V.- BRICK MAKING.
THE following ia not intended as a description of tho art, as practised in towns, whore the procese is faoili* tated by various applianoos, whioh would bo costly to provide for a limited number ; but describes tho usual way in which bricks are made in the bush. In townB bricks are sold at so much per 1000, delivered ready for use. In the bush the common practice is to count the bricks on tho hook, before burning ; an aooount is taken of tho number moulded, after which the oontraotor burns thom, bnt accepts no responsi bility as to the result; exoepting that they aro sup posed to be properly burnt, whioh can only be ascer tained by opening somo parts of the kiln after it has cooled. The reason of this is, that a considerable time may elapse before the bricks aro used, and tho briokmaker leaves to fulfil other engagements'. If
] BBICKMAKING.-FIG 1. .1
possible it ia more satisfactory to agree tor so muob per 1000,. only for snob, bricks aa are fit for building. Of course,.in sucha case, the pride would be higher, as th« outside casing bricks are useless. If the number, required ia sufficient for two or three kilns, there ia this advantage,- that the easing bricks may be roburnt. In making agreements it i* neoessary to state dis tinctly who «nts and carts the firewood; who provides covering for the haoks, or fences them in, and that the contractor is responsible for any damage, aa it often happens the bricks may be oraoked and useless from carelessness in keeping them covered at proper times, or washed out of all shape from showers of rain. The briokmaker should be a thoroughly shilled tradesman, and even by pay ing more per thousand it is better to secure such a man. Aa an instance, I may mention that in the neighbourhood of Deniliquin I have known brick makers fail in making a good brick, and blame the clay; and another experienced man go to the same place and mike a first-olass brick. 1 have much pleasure in Btatin? that I allude to the. well-known briekmaker Mr. Hodgkin?, and having used over a million: from him I am abie to say that I have never seen a better brick in any of the colonies. It is desirable that the employer should understand come thing of the nature of brick earth, aa on the seleotion of this almost everything depends ; the subsequent operations being matters of mechanical routine, except in barning, where experience is again required. Pu1*.day moulds easily, but shrinks and cracks on the hacks; and in the kiln rends and warps, although by theaotionof the fire it becomes very hard. This is avoided by the addition of sand or loam, bat there are few localities whore a mild clay, suitable for the pur pose, may not be found. The colour depends on the ohemical composition of the earth employed, and not its natural colour before bu ning. The presence of oxide, of iron, without lime or similar substances, produces a red tint. The addition of lime changea the red. produced by the oxide of iron to a cream brown, while magnesia brings it to a yellow. Some clays burn to a olear white. Stones or pebbles must be avoided, as they cause the briek to crack, in drj - ing, and make it elaky when burnt. A piece of lime
stone no bigger than a pea would destroy a brick:
; ¿v.« «.:~ "_:Ji ir, -- "« i- AI. _
tue carbonic aoia ia ari ven off by the heat, and foroea a vent through tho side. In tempering clay for a small quantity, it may bo turned over repeatedly with ahovela, . water baing added aa required, and trodden
by men or horses until it acquires the requisite plaptieityt
?I A pug-mill Bavoa a lot of labour, and . secures a botter olacs of brick. Fig. 1 is an
illustration of ono. It ia simply a wooden ? tab, 'smaller at tho bottom than top, with
an upright revolving shaft passing through ita centre, to which are keyodla number of knives, which, by their motion, ont and ."knead the clay, and force it gradually -through the miil, whence it should Uauf|in a
thoroughly tempered state; fit for tho uso of : the moulder. The mill is worked by horse
power, a beam loft or 20ft long, to whioh the horao i* attached, be ing fixed to the upright
Fig. 2 also shows the mill in acotion. The briokmould ÍB a kind of box, without top or bottom, made somewhat larger than the intended size of a brick, to allow for the clay ?brinkin? ; tho proportions shonld also allow for the joints. The proper size of a brick is Oin x 4\i'm x 3'n. The mould should bo 9}in x4}inx 3£ n. This should be stated in the agreemaut, with prioe of rations, &o., and theao eeveral oonditiona being daly provided for diapnes, whioh are muoh too common, wi 1 ie prevented. |Tho mou'd is usually mada ot' wood, plated with iron round the edges. Thov aro
BomotimcB ruado of iron or brass. Cato should be tnkoa that the sidos aro Bnffioiout'y Btiff, not to spring, when the olay is dossed into it. Tho strike is a small pieco <>f wood about lOin long x li'in wide and Jin thick, und it is nsod to lemovo tho BuperiluonB oarth in tho ryooesH of moulding. Tho pallotB aro pieoes of hoareJ a thiok, and of tho oxaot width of tho mould, but ab<"-ut tHn loneor. Thoho.ok barrow, or off bearin? barrow, na it ia gonai ally toriroi. ia a light Irurno. supporting a light too of lattioo work, on which tho b iokB aro plaoid in two parallel rows of 13 euch, and thus whoelod to tho hao'cfl. Gre*t o >ro ij rioo.'Hinry in off-bearing aa tho bricks easily boco mo mi^shai cd from careless handl ing in thiB tta.e of their manufacture.
Tho hack ground should be a olear level Bpace,
slightly falling towards the kiln, to lessen tba labour of wheeling, and for the purpose of drainage. The fonndations of the haoks are slightly raised. The hacks shonld be lift apart from centre to centre, and the length proportionate to the number of bricks to ba made. A oovering muBt bo provided to shelter the bricks from sun, wind, rain, and frost. Tho beat is a long tarpaulin of old bogs or canvas th own over a ridgo, and scoured with lanyards to pegs in the
In the abeenco of this, straw, roods, or any similar material may be used, thrown lightly on top of the
Tho moulding table is Bimply a rougb erection, furnished with a water trough, in whioh the mould is dipped eaoh time utter using. Sometimes this is
mounted on wheels, and forma what is termed a bow- , ling stool. In this case the moulder place s the brioks on tho haoks himself as ho monlds them, wheelisg the table along aa >£ quired. When the barrow is loadeJ, dry sand is sprinkled over tho tricks, and they are carefully wheeled to tho hack ground. _ Tho off bearer then takes a tparo pallet, a td places it on one of tho bricka, whioh he caines between the two pallets to the hack, and sets it up carefully edge ways ; taking care in removing the pallets not to injure the shape of the soft brick. One of tho pallets is replaced on tho barrow, and with the other another briok ia removed; and tho proozsa ia repeated till the 26 bricks havo been placed on tho hacks, when the empty barrow is wheeled back to the moulding table. In the meantime another barrow has been loaded, and ia ready for wheeling to the haok ground.'. Three haok barrows ar« usually required, so that"one of them is constantly being unloaded on the hack ground, another loading at the moulding table, ard the third being wheeled to and from tho back ground. Thua two men are employed wheeling and hacking. The hacks are sot up two bricka in width. After the bottom of one row ia completed, a Eooond hack is began, to give tho bricks time to harden before a second course is laid on them ; ana when tho second course is oommonoed, tho bricks must be placed fairly on each other, or they will fco marked, whioh injures' their appearance.
1 Dtyinar requires great caro and attention, to allow
each briok to dry uniformly from tho faco to the heart. They are sprinkled with sand to absorb superfluous moisture, and render them IOBB liable io be cracked by the sun's rays. The amount of expo sure on the hacks must be regulated by the nature of the day. Tho hacks are carried up in thiB way until they are eight bricks higb, when they are lett for a few days to harden. . When half dry they are acintled, that ia set further apart, to allow the wind to pass freely between them, and thoa they remain till sufficiently dry for burning. Tho time required for drying varies from two to four weeks, according
to the weather. '
Burning.-Much depends on tho setting of tho kiln, as there is a fereat deal of art in arranging the bricks to allow tho heat to be equally diffused through tho kiln, and to afford a proper draught ; BO as to obtain the greatest amount of steady heat, with tho smallest expenditure of fuel. Narrow openings are left in tho lower part of the kiln, forming flues, con
necting the opposite fire holes ; the* tops of. thees flues being formed by oversailing the;brioks on each side till they meet. ^ These flues are the eame height
as the fires holes.
The bricks are not placod close together, but a space is left all round eaoh brick to allow of the pas sage of the heat round it; the bricks in the succes sive oourses being orosaed, either slantwise, or at right anales to eaoh .other. When it is wished to produce bricka of a uniform iel tint, the fáoes and .ndaof tho bricks are kept inoloae contact, crossing them every few courses only. The kiln being topped at a height of about 4à conrees, tho outside ia plae* tered over with clay, to prevent the admission of current s of cold air; and the fires being lighted, the heat is got up gradually, care being taken not to urge the fires matilall the steam is driven off from the bricks, and the aotual burning begins. , When the
tiro'has attained its full heat, tho fire bolos are > partially stopped with day, and tho top of the kiln id
covered over with earth, tmf, or boards, to cheek the - draught ; and a steady uniform heat ia kept up until the completion of the burning, which generally otoo« pieB threo days and three nights from the first light ing ot' the fircB ; at the expiration of whioh time, the
fire holes are aompletely Btopped, and the.fires put . ont. The kiln should then bo allowed to cool ver» gradually, as tho sonndnesB of tho bricks is-muon deteriorated by the kiln being opened too soon. In forming the kiln the necessary Bisse, calculate 10 bricks to a cubic foot. The process above described is for the manufacture of what aro tet med slop bricks, I Tbere are othor modes of making and burning, whioh I it is not neoassary to describo, aa thiB ia the plan beat adapted for tba bosh. Tho vitrified brioks round the fire holes are best adapted for fonndations ; the pale ones near the outside of the kiln wonld be best used for inside work, and tho bose coloured brioks for out side work, Care should be taken in loading and unloading, not to chip the edgeBof the bricks, BB thia spoils the appearance of the building.
It may bo nsoful to state in thia place, in order to arrive at the size of the kiln, that about 4500 brio'iB aro required fora rod of briok work, which means 5£ square yards of 14in work. Or an easier method of computing would be to reckon the number of square yarda of din work in the walls and founda tions of tho proposed building, and allow 100 brioks for eaoh square yard. B. ioks should be rectangu lar, aonnd, and well burnt; and when struck to gether, ring with a metallic Bound. Deficiency, in any of theso points indicates an inferior, briok. Brioka tor staining wells should bo moulded accord ing to the segment, splayed brioks for arob.es, roveals, &c. can also be monlded.
BURNED BALLAST.-In some parts of tho country, especially on the vast plains of Riverina, such a thing as a stone is not to bo found for hundreds of mile«. For metalling roads, and for concrete and other purposes, vitrified day is often substituted. Unless burnt in a lem'ar kiln, the process is a some what critical ono. As muoh ns £1 por cubic yard has boen paid for broken metal of thiB description, and largo quantities are used for forming streets whero ßtono is not to bo _ proonred. It is often necessary to burn thia in isolated places, for ap proaches to brid goa, and the following ia tho best plan: Select the most fusible earth; available ; tho best is strong olay, containing lime, oxido of iron or other fluxes. ThiB fusoa at a moderato heat, and melts into a gr boniah blaokolay. If possiblo, sink a piton the bank of a crook, and tunnel a holo through the Bide. This forms a simplo fui naco with a good d aught. Temper tho o'ay, out it into any shaped blocks, and let it dry. Placo a layor of dry loga and small wood for kindling, at iho bottom of the pit, on this a layer of clay lumps ; then another stratum of logs ard clay alternately to tho top. Light the bottom tier, and when tho whole mass ia at a red heat, cover it in tho same manner an denoribed for tho brick kiln. When cool, tho clay will bo found tnsrdinto a vitrified mass, harder than bluo etona.
Ir, ia hard work to break it up. bufc it forms very , duiablo metal. Anotl or plan, ia io build a rough) kiln with moulded bricks., and on tho whole thiB if porhaps tho bettor flan,