Builder’s Dictionary 1734/II

The Builder’s Dictionary: Or, Gentleman and Architect’s Companion. Explaining not only the Terms of Art In all the several Parts of Architecture, But also containing the Theory and Practice Of the Various Branches thereof, requisite to be known by Masons, Carpenters, Joiners, Bricklayers, Plaisterers, Painters, Glaziers, Smith, Turners, Carvers, Statuaries, Plumbers, &c. II, London [Arthur Bettersworh – Charles Hitch – Stephen Austen] 1734.

Mortar, Morter

MORTAR, MORTER [in Architecture] is a Preparation of Lime and Sand, mixt up with Water, serving as a Cement, and us’d by Masons and Bricklayers in Building of Walls of Stone and Brick.

For Plaistering of Walls, they make their Mortar of Lime, and Ox or Cow Hair, tempered well together with Mortar.

Of making common Mortar]

As to the Proportion of Lime and Sand to be us’d in making common Mortar, there are different Opinions.

Vitruvius says, you may put three Parts of Dug (or Pit-Sand) to one Part of Lime; but if the Sand be taken out of a River, or out of the Sea, then two Parts of it, and one of Lime. He also adds, that if to the River or Sea Sand, you put one third Part of Powder of Tiles or Bricks, it will work the better.

But Vitruvius’s Proportion of Sand seems too much, tho’ he should mean of Lime before it is flak’d; for one Bushel of Lime before ’tis flak’d, will make five Pecks, after ’tis flak’d.

About London (where for the most Part Lime is made of Chalk) they put about 36 Bushels of Pit Sand to 25 Bushels of Quick Lime, that is, about a Bushel and a half of Sand to a Bushel of Lime.

In some Places they put after the Proportion of three Pecks of Sand to one Bushel of Lime; in other Places a Bushel and half of Sand, to a Bushel of Lime.

In Effect, the Proportion of Lime to Sand in making of Mortar, ought to be according to the goodness or badness of these Materials, and is therefore rather to be regulated by the Judgment of experienc’d Workmen in each particular Country, than by any stated Proportions of Materials.

As to the Method of making of Mortar],

Some Workmen are of Opinion ’tis the best Way not to use Mortar as soon as it is made; nor (in making it) to make the Lime run before it is mix’d with the Sand (as some do) but rather to throw the Sand on the Lime while it is in the Stones, before it is run, and so to mix it together, and then to wet it; by which Means (they say) it will be the stronger, and when it has lain a while before it is us’d, will not be so subject to blow and blister.

Others advise to let Mortar (when made) lie in a Heap two or three Years before it is us’d, which they say, will render it the stronger and better; they likewise say, the using of Mortar as soon as ’tis made, is the Cause of so many insufficient Buildings.

Others advise, that in slaking of Lime, to wet it every where but a little (and not to over-wet it) and to cover every Laying or Bed of Lime (about the Quantity of a Bushel) with Sand, as you flake it; that so the Steam or Spirit of the Lime may be kept in, and not fly away, but mix itself with the Sand; which will render the Mortar considerably stronger, than if it were all flak’d at first, and the Sand thrown on altogether at last.

2. That all the Mortar should be well beaten with a Beater, three or four times over, before it is us’d, by that Means to break all the Knots of the Lime well together; and they say, that the Air which the Beater forces into the Mortar at every Stroke, conduces very much to the Strength of it.

3. That when you design to build well, or use strong Mortar for Repairs, you beat the Mortar well, and let it lie two or three Days, and then beat it well again, when it is to be us’d.

4. That Mortar be us’d as soft as may be in Summer Time; but pretty stiff or hard in Winter.

As to mixing and blending of Mortar, Mr. Felibien observes, that the ancient Masons were so very scrupulous herein, that the Greeks kept ten Men constantly employ’d for a long Space of Time, to each Bason, which rendred it of such prodigious hardness, that Vitruvius tells us, the Pieces of Plaister falling off from old Walls, serv’d to make Tables.

And Mr. Felibien tells us, ’tis a Maxim among old Masons to their Labourers, that they should dilute it with the Sweat of their Brow, i. e. labour it a long Time, instead of drowning it with Water, to have done the sooner.

Mr. Worlidge advises, that if you would have your Mortar strong, where you cannot have your Choice of Lime, but can chufe your Sand and Water, not to use that Sand that is full of Dust; for all dusty Sand makes the Mortar weaker: and the rounder the Sand is, the stronger the Mortar will be, as is usually observ’d in Water drift Sand; that it makes better Mortar than Sand out of the Pit.

Therefore he advises, that if you have Occasion for extraordinary Mortar, to wash your Sand in a Tub, till the Water, after much stirring, comes off clear, and to mix that with new Lime, and the Mortar will be very strong and durable. And if the Water be foul, dirty, or muddy, the Mortar will be the weaker.

Wolfius observes, that the Sand should be dry and sharp, so as to prick the Hands when rubb’d; yet not earthy, so as to foul the Water it is wash’d in.

He also finds Fault with Masons and Bricklayers, as committing a great Error in letting their Lime slacken and cool before they make up their Mortar, and also in letting their Mortar cool and die before they use it; therefore he advises, that if you expect your Work to be well done, and to continue long, to work up the Lime quick, and but a little at a Time, that the Mortar may not lie long before it be us’d.

So that it appears, Men differ in their Opinions in this Point; some affirming it to be best to work up the Mortar new, and others, not till it has lain a long Time.

A certain Author tells us, that an experienc’d Mason told him, that being at work at Eridge-Place, (at the Lord Abergaveny’s) at Fant in Sussex, they would have him make Use of Mortar that had been made four Years. But when he came to try it, he said it was good for Nothing, because it was so very hard, that there was no tempering it. Upon which, a certain Jesuite (who resided in the House, and had been a great Traveller) told him, that to his Knowledge at several Places beyond Sea, they always kept their Mortar 20 Years before they us’d it; but then this Mortar was kept in Cisterns for the Purpose, and always moist.

The Ancients had a Kind of Mortar so very hard and binding, that after so long a Duration, ’tis next to impossible to separate the Parts of some of their Buildings; tho’ there are some who ascribe that excessive Strength to Time and Influences of certain Properties in the Air, which is found to harden some Bodies very surprisingly.

De Lore observes, that the best Mortar is that made of Puzzuoli; adding, that it penetrates black Flints, and turns them white.

The Lime us’d in the ancient Mortar is said to be burnt from the hardest Stones, and even the Fragments of Marble.

As for the scaling (or crimping) of Mortar out of the Joints of Stone and Brick Walls, some are of Opinion it proceeds from the badness of the Sand or Lime, or both, as well as from the Season of Year when Work is done.

Besides the common Mortar us’d in laying Stones, Bricks, &c. there are several other Kinds, as

White Mortar, us’d in Plaistering the Walls and Ceilings, which are often first plaistered with Loam, and is made of Ox or Cow Hair, mix’d and temper’d with Lime and Water, without any Sand.

The common Allowance in making this Kind of Mortar is one Bushel of Hair to six Bushels of Lime; the Hair serves to keep the Mortar from cracking; binding it, and holding it fast together.

The MORTAR us’d in making Water Courses, Cisterns, &c. is very hard and durable, as may be seen at Rome at this Day. It is us’d not only in Building of Walls, but also in making of Cisterns to hold Water, and all manner of Water Works, and also in finishing or Plaistering of Fronts, to represent Stone Work.

There are two Kinds of it, the one is compounded with Lime and Hogs Greafe, and mixt with the Juice of Figs; and the other is of the same Ingredients, but has liquid Pitch added to it, and is first wet or flak’d with Wine, and then pounded or beaten with Hogs Greafe, and Juice of Figs.

That which has Pitch in it, is easily distinguish’d from the other by its Colour; and what is plaistered with this Kind of Mortar, is wash’d over with Linseed Oil.

Mortar for Furnaces, &c. is made with red Clay, wrought in Water, wherein Horse Dung and Chimney Soot has been steep’d, by which a Salt is communicated to the Water, binding the Clay, and making it fit to endure the Fire: This Clay ought not to be too fat, lest it should be subject to Chinks; nor too lean or sandy, lest it should not bind enough.

Some Operators in Metal, use a Kind of Mortar to plaister over the Inside of their Vessels in which they refine their Metals, to keep the Metal from running out; and this Kind of Mortar is made with Quick-Lime and Ox-Blood; the Lime being first beaten to powder, and sifted, and afterwards mixt with the Blood, and beat with a Beater.

The Glass-makers in France are said to use a Sort of Mortar (for plaistering over the Insides of their Furnaces) which is made of a Sort of Fuller’s Earth, which is procur’d at Beliere, near Forges, which is the only Earth in France that has the Property of not melting in this excessive Heat; and also the Pots which hold the melted Metal, are made of this Sort of Earth, and will last a long Time.

Mortar for Sun-Dials on Walls, may be made of Lime or Sand tempered with Linseed Oil, and for Want of Linseed Oil, may be made of scumm’d Milk; but Oil is better; This spread upon the Wall, will harden to the hardness of a Stone, and not decay in many Years, and will endure the Weather six times as long as the ordinary Plaister, made of Lime and Hair with Water.

A certain Author says he has known a very strong and tough Mortar (for a Sun-Dial Plane) has been made after the following Manner.

There was taken five or six Gallons of Brook Sand, and dry’d on an Oast; and after that sifted through a fine splinted Sieve, and then mix’d with it the same Quantity, or rather something more of sifted Lime, and a Gallon of Boring (or Gun) Dust sifted also; these were all wetted and well tempered with six or seven Gallons of scumm’d Milk, and about two Quarts of Linseed Oil.

This was laid on the Wall first, well wetted with Milk; but this prov’d very troublesome to the Workmen to set it smooth, by Reason that it dry’d so very fast; but by keeping it often sprinkled with Milk, and smoothing it with the Trowel, it did at last set with a smooth and shining Surface.

But notwithstanding all his Care (as it dry’d) it crack’d pretty much, which might probably proceed from the Want of Hair to it; it did also blow Blisters, tho’ the Lime was sifted; which probably might have been prevented, if the Lime had been prepar’d as for Fresco Painting.

Extraordinary good Mortar for Floors, Walls, Ceilings, &c.

Temper Ox Blood and fine Clay together, then lay the same in any Floor, or plaister any Wall or Ceiling with it, and it will become a very strong and binding Substance. This is said by some to be much us’d in Italy.

In Buildings one Part of waste Soap Ashes mix’d with another of Lime and Sand, make a very durable Mortar. This Mortar may be made, as it was by a certain eminent Soap Boiler, who built himself a very handsome House with it in the following Proportions; two Load of waste Soap Ashes, one Load of Lime, one Load of Lome, and one of Sand.

Another Person of the same Trade us’d only Lime and Soap-Ashes, tempered and wrought together for Mortar; with which he laid both the Foundations, Chimnies, and their Tunnels, in his Dwelling-house in Southwark; which have endured and stood out those Storms which have overturn’d many other Tunnels, both new and old, which were built with common Mortar.

It is true indeed, this kind of Mortar is somewhat rough in the laying, and more sharp and fretting to the Fingers than common Mortar; which may be the Reason why it is so much neglected and decry’d by Workmen.

But these two Inconveniencies might be easily remedied; and indeed its Roughness is so far from being a Fault, that it is rather an excellent Quality in the Mortar. But this may be remedied, by grinding or stamping the Soap-Ashes (which are in hard Cakes) to a fine Powder, before they are mix’d with the Sand, which will soon bring it to a smooth Temper.

Nor will the Charge be much; the Profit of one Day’s Labour will answer the Charge of three Mens Wages, in the Difference of Price that will be found betwixt one Load of these Ashes and one Hundred of Lime.

Secondly, As to the Sharpness wherewith it offends the Workmens Fingers, that may be avoided by wearing Gloves (without which they seldom lay any Brick at all) to avoid the like Effects which they find in Lime.

Or, for an assured Remedy in these Cases; these Ashes may be re-imbib’d in Water for a considerable Time, till more of their Salt be extracted from them; and then much of their fretting Nature being taken away, they will be found to be gentle enough.

For laying Tiles, in some Places they make a kind of Mortar of Lome and new Horse Dung well tempered and mix’d together: And this is by some Workmen accounted a good, strong, and cheap Mortar, which is more suitable to Tiles than the common Mortar made with Lime and Sand, which they say corrodes and frets the Tiles, and causes them to scale and fly to pieces; which this does not.

For the plaistering the Fronts of Houses in imitation of Brick-work; Some Workmen make Mortar for this sort of Work, of Powder of Brick, sharp Sand and Lime, and some red Oker. Some Houses plaistered with this kind of Plaister, look very well, tho’ they have been done 20 or 30 Years, and may be taken, by one passing by, for a Brick House, tho’ it be only Timber plaistered over. The Workman has for this sort of Work commonly 1 s. per Yard, only for Workmanship.

How much allow’d to a Rod of Brick-work, or a Square of Tileing.]

Workmen usually allow a Hundred and half (or 37 1/2 Bushels) of Lime, and two Load (or 72 Bushels) of Sand) to make Mortar enough for a Rod of Brick-work.

And for Tileing; four Bushels of Lime, and six or eight Bushels of Sand, will make Mortar enough for laying 1000 of Tiles, which is about a Square and a half; so that a Square of Tileing will take up, for Mortar, about 2 2/3 Bushels of Lime, and about five Bushels of Sand.

A Caution.]

It is a general Caution in all Parts of a Building, that where either Stones or Bricks are contiguous to Wood, they ought to be laid dry, or without Mortar; because Lime and Wood are unsociable; the Lime very much corroding and decaying the Wood.

Painting in Oil

PAINTING [in Oil] the Art of Painting in Oil, was unknown to the Ancients, and was first discover’d and put in practise in the Beginning of the XIV Century, by a Flemish Painter, nam’d John van Eyck, or John de Bruges. Painting before his Time, was all perform’d in Fresco or Water Colours.

This Invention was of very great Use to the Art of Painting, since by Means hereof, the Colours of a Painting, are preserv’d much longer and better, and receive a Lustre and Sweetness, which the Ancients could never attain to, what Varnish soever they made Use of, to cover their Pieces.

The whole Secret consists only in grinding the Colours with Nut-Oil or Linseed Oil: but the Manner of working is very different from that in Fresco, or in Water, by Reason that the Oil does not dry near so fast; so that the Painter has an Opportunity of touching, and retouching all the Parts of his Figures, as often as he pleases; which in the other kinds of Painting is a Thing impracticable.

And besides, the Figures in this Way of Painting, have more Force and Boldness, in as much, as the Black becomes blacker when ground with Oil, than with Water. Besides, that all the Colours mixing better together, render the Colouring sweeter, softer, more delicate, and give an Union and Softness to the whole Work, which is inimitable in any of the other Manners.

Painting in Oil, is perform’d on Walls, Wood, Stone, &c. To paint on a Wall, when it is well dry, they give it two or three Washes of boiling Oil, till the Plaister remain quite greasy, and will not imbibe no more. Upon this they lay drying Colours, viz. white Chalk, red Oker, or other Chalks, beaten pretty stiff. When this Couch or Lay is well dry, they sketch out and design the Subject to be painted, and at last paint it over, mixing a little Varnish with their Colour, to save the varnishing afterwards.

Others to fortify the Wall better against Moisture, cover it with a Plaister of Lime, Marble Dust, or a Cement made of beaten Tiles soak’d in Linseed Oil; and at last they prepare a Composition of Greek Pitch, Mastick, and thick Varnish boil’d together, which is apply’d hot over the former Plaister: When this is dry, they lay their Colours on as before.

Others make their Plaister with Lime, Mortar, Tile Cement, and Sand; and when this is dry, they lay on another of Lime, Cement or Machefer, or Iron Scum; which being well beaten and incorporated with Whites of Eggs and Linseed Oil, makes an excellent Couch or Plaister, on which when it is dry, the Colours are laid as before.

In painting on Wood, they usually give their Ground a Couch or Lay of White, tempered with Size; or they apply the Oil above-mention’d: the Rest is after the same Manner as in painting on Walls.

To paint on Linnen or Canvas.

The Canvas being stretch’d on a Frame, they give it a Couch or Lay of Size: When it is dry they go over it with a Pumice-Stone, to smooth off the Roughness. The Size lays all the little Threads and Hairs close on the Cloth, and the little Holes are stopp’d up, that no Colour can come through.

When the Cloth is dry, they lay on Oker, which is a natural Earth, and bears a Body, sometimes mixing with it a little white Lead to make it dry the sooner, and when it is dry, they rub it with a Pumice Stone to make it smooth.

After this, sometimes is added a second Lay, compos’d of White Lead and a little Charcoal black, to render the Ground of an Ash Colour; taking Care in each Manner to lay on as little Colour as possible, that the Cloth may not break, and that the Colours when they come to be painted over, may preserve the better.

Therefore as little Oil as possible is to be us’d, if you would have the Colours keep fresh; and therefore some mix them up with Oil of Aspic, which evaporates immediately, and serves to make them manageable with the Pencil.

To paint on Stones, it is necessary to apply Size, as on Cloth; it will be sufficient to add a slight Couch of Colours, before the Design is drawn.