TAR and Pitch in Ship-building being generally used by the Calkers, I shall therefore put in what I have to say on shuch Materials, subjoining it to their Branch of Duty.
Tar is produced from the Knots of Fir-Trees, by a sort of Distillation, and of Tar Pitch is made by boyling the Tar, whereby it becomes stiffer and drier.
The Price of the imported is generally as 3 to 2, that is, if a Barrel of Pitch is valued at 30 s. a Barrel of Tar is valued at 20 s. and the common Weight of a Barrel of Pitch is 3 Hundred, or rather something more than less, meaning Gross Hundreds. The Barrel of Tar is also 32 Galleons, or thereabouts, and each Gallon is counted 282 Inches, which in 32 Gallons amounts to 9024 Inches; also a Gallon of Tar is 10 Pound and a half 3 so that the Weight of a common Barrel of Tar should be 336 Pound, and the Barrel of that is 56 Pound. The Cubick Feet in a Barrel of Tar is 5 Foot and 2/3 [?] of a Foot, and in a Barrel of Pitch the Feet are 4, which being 6912 Inches, the Difference in Inches between a Barrel of Pitch and a Barrel of Tar is 2112 Inches, which is the Number of Inches contained more in a Barrel of Tar than in a Barrel of Pitch; from which the Proportion of Inches will be as 13 to 10, but the Proportion of the Weight in common Barrels of Tar and Pitch is generally equal: That its very probable that a Barrel of right good Tar will produce one Barrel of right good Pitch, according to their various Content afore-mention'd, or 24 Gallons and a half, which is according to the Number of Inches contain'd in a Barrel of Pitch; from which it appears, that the Waste in Boyling will be 7 Gallons and a half, or near ¼ of the whole 3 which ¼ Waste, together with the firing, fitting Utensils, and Day Labour to make it, may be deem'd 1/3; and this Observation will be very agreeable to the different Price, provided it was, as it must needs seem to the Contractors, that the Cubick Feet in a Barrel of Pitch were equal to the Cubick Feet contain'd in a Barrel of Tar, since their Weight is equal one to another, but the Case is quite different; tho' the Weight be equal and alike, the Gallons are as 13 to 10, as well as the Number of Inches, and therefore this 1/3 Differences in the Price is purely advanced for the Firing and Labour, and the Utensils fitting to Boil it, since the Waste made by Boiling is allowed in the Difference there is between the Barrels; of which I shall more particularly consider hereafter.
Mr. Evelyn in his Sylva tells us, that one Mr. Winthorp presented the Royal Society with a Process of making Tar and Pitch in New England, which he thus abreviates. Tar is made out of a sort of Pine Trees, from which naturally Turpentine extilleth, and which at its first flowing out is Liquid and Clear; but being hardned by the Air, either on the Top of the Tree, or wherever it falls, is not much unlike the Burgundy Pitch; they grow upon the most barren Places: Of Tar, by Boiling to a sufficient Height, is Pitch made, and in some Places where Rosin is plentiful, a fit Porportion of that may be dissolved in the Tar whilst it is Boiling, and this Mixture is soonest converted to Pitch; but it will be somewhat of a different kind from that which is made of Tar only, without other Composition: However, the way for Dispatch and sudden Use is to heat the Tar very hot, and set it on fire, which it will very easily do, letting it burn so long, till taking out some small Quantity for Tryal, being cold, it appears of a sufficient Consistence; then covering the Kettle close the Fire is extinguish'd, and the Pitch made without any more Ceremony. There is a Process of making Rosin also out of the Knots, by splitting them out into thin Pieces, and Boiling them in Water, which will Educe all the Resinous Matter, and that will harden into Rosin. He concludes the Discourse by telling how he is of a strong Opinion, that the Pines and Fir Trees in Scotland might yield her Majesty plenty of excellent Tar, were some iudustrious [sic] Person employed about the Work.
Our Chymical Shipwrights will tell us, that they can with some Mixture put in at Boiling the Tar, produce 5 Barrels of Pitch out of 6 Barrels of Tar; then 6 Barrels of Pitch containing 24 Foot, and 6 Barrels of Tar containing 31 Foot and 1/3 of a Foot, the Product in Feet is near ¾; and if so, it would be much cheaper to have all Tar transported, and make Pitch of it in England, since for every 8 Pound you would have 9 Pounds worth of Goods, which would be one Pound advanced in 8 for Labour and Fewel, and would really turn to Account in a large Quantity of such Materials; but referring such Chymical Observations to be more fully considered by the Chymical Inquirers, I shall just instance what I have observed in a Tryal made in his Majesty's yard at Deptford on his Majesty's Ship the Tilbury; but before I proceed it will not be very improper to give an Account of the Source of tryals in General, but more particularly of this.
You may observe, that the World began with Project when there was but three Persons in it, as we may read in Sacred History: They grew outragious purely about the Notion they had of their Ability, one envying another, and furiously disputing which was the greatest Proficient in his particular Art and Science, that he more immediately practised; which Temper in Men, as it first was introduced with Mischief and Envy, so it still continues in Disorder, since every Man is puff'd up with a Notion of his Ability, tho' it be ever so mean, and the Opinion which the general Part of Mankind has of him, be ever so contrary to his own.
But not to insist any farther on Project in General, I shall proceed to shew the Occasion of the Tryal that is before-mention'd, which was to cover a Ship with such a Mixture under Water, that should preserve the Plank from the Worms, without covereing her with Sheathing Board, which is our greatest Preservative against that Animal, observing not only how Chargeable the Sheathing of Ships Bottoms is, but also that its very pernicious, and altogether destructive to the Ship's Planks on which it is nail'd; the Plank at the Sheathings being pull'd off, is not much better for Service (provided another Sheathing is not applied) than if the Worm had eat the same, since the Nails will as effectually split and tear the Plank to Pieces, as the Worm will eat it to Pieces, and therefore in very small Ships the Difference will not be much, whether you shift all the Plank in the Ships Bottom, or put on a new Sheathing.
Indeed such Faculties, which are generally incident to Ships, has put several (besides this Gentleman) upon Thoughts how to prevent such Disorder in the Machine, believing if they could propose any thing that would be in any manner serviceable to the Publick, they should be suitably rewarded for doing the same.
However, the Mixture being proposed to be highly necessary for preserving Ships Bottoms from the Worms, it is accordingly try'd; but as to the Proof I never inquired: However, it was a very hard Mixture, almost too hard to be melted with a mean Fire, and being laid on upon the Ship like polishing, so very thin, scarce discernable to Appearance that the Plank was any ways covered, only by glistering; but suspending such Chymical Preparations at present, I shall proceed to give same necessary Cautions towards the Use of the common Pitch and Tar, and also in Merchandizing for it.
I say in Merchandizing for Pitch and Tar, great Care ought to be in buying such as is prime good, for Defects in either is very detrimental to the Managers, since I have observed one great Trick in Tar, and that is to make good the Wants that may happen (by Leakage or Waste) with Fir Saw-dust; but however, that Sham is very easily discovered, not only by the Thickness of the Tar, wherein you may perceive that there is some Dust in it, but by weighing of it you may exactly know how much right good Tar there is contained in the Barrel, and how much Saw-dust, or any such adulterated Matter that there is in the same, since Saw-dust of Fir (altho' of the same Consistence) is much lighter than the Juice that flows from it, and therefore all that you have to do is to know the Specific Gravity of each, which will guide you in knowing whether what you are Merchandizing for agrees with such a Standard, according to the Quantity you are dealing for, which will make you safe and sure that the Commodity is of a right good sort: Notwithstanding a nice Inspection may do without such Tryals, since the true Juice and well distill'd Tar must certainly appear bright and very clear, like a perfect Liquid Substance that flows from a Limbeck.
I doubt not but that there are some other Artifices to mix and adulterate such a Commodity, to the Advantage of a tricking Vendor, all which being highly detrimental to the Buyer, and therefore worthy of Inquiry, since the Damage will not only rest in the Tar, but it's also a Loss in making the Tar into Pitch, and as commonly practised as can be, to make Pitch out of damaged Tar; but however that must be done by those well accustomed in doing it, since it's really very hazardous to make Pitch from Tar that is not very good.
I have in Virginia attempted to make Pitch from damaged Tar; but as soon as ever the Tar grew hot, all the Artifice in Nature could scarce keep any in the heating Pot, altho' I scarce covered the bottom. I have also set the Tar on fire to prevent it's rising, and dropped the Tar into the Pot by (seemingly) Spoonfuls, and yet notwithstanding could not save the ¼ Part of what is generally made with right neat Tar.
Such Commodities rise and fall in the Price, according to the Times and Seasons of obtaining them; for they being chiefly brought from Foreign Parts, it cannot be reasonably expected otherwise, but that the Advantage will be made according to the Scarcity and Necessity they observe in others; so that at some times Tar is sold for 20 s. and Pitch in proportion to that Price, as 3 to 2; whereas at other times Tar rises in Value to 40 s. a Barrel, and Pitch in proportion as aforesaid; so that there is 20 s. advanced by the Difficulty that will be always found in dealing with a Stranger, besides the hazard that is run in the Quality of the Material, as in all likelyhood to be deprived of having neat Goods, or otherwise the true Juice that is distilled from Pine Timber; and since Vriginia, New England, Newfoundland, nay, our own Kingdom of North Britain, can afford us as good Tar, and from that as good Pitch, as any that is brought from the East Kingdoms, it is not Necessity that obliges us to be beholding to others for such Commodities as our own Land doth abound with, but the neglecting of our own Manufactures, and encouraging Strangers in theirs.
All which and much greater Advantages may be made by this excellent Juice, were there (as Mr. Evelyn says) industrious and skilful Persons imploy'd about the same.
I shall just instance what Quantity of Pitch and Tar may be expended in the Royal Navy every Year (presuming that there may be double that Quantity expended in the Concern of our whole Kingdom of Great Britain and Ireland) from which may be plainly seen what Advantage is made, and Money expended to purchase this one Material in Ship-building and Rebuilding.
In the first Place I will mention how often any Ship ought to be clean'd and dress'd, so as to preserve her Bottom, and make her useful.
Secondly, what Quantity of such Materials may be used on each particular Ship at such Dressing; and thirdly, the Number of Shipping there is to be so trimm'd, with the Total Expence.
First them if a Ship is employ'd in the Sea Service, she ought to be clean'd and dress's every 12 Months at the farthest, if it be possible; which Method of preserving them neat and wholesome, will not only preserve the Health of her Men, by Lodging them warm and in good Order, but it will also add to the Motion of the Machine, and make her to Sail much swifter; but on the other hand, if the Ship is laid by and in a Harbour, then once in three Years may be sufficient to dress her Bottom, but still to continue the Practice of dressing and preserving the Upper Work every Summer Season.
Again, if a Ship is in a Cruising Station, as most Men of War under 90 Gun Ships generally are, then such ought to be clean'd under Water once in Two Months at farthest, and at such Cleaning they ought to be dried with Reed or Brrom, just to melt in the Pitch, and harden the Plank; so that a little Tallow will be sufficent to preserve such a Ship's Bottom 12 Months, and at the Expiration of that Time they ought to be new cover'd with Pitch, or Rosin and Oyl.
I shall therefore allow a Coat (as it sometimes term'd) of Pitch to every Ship in England (that's in the Publick Service) under a Ship of 70 Guns, once in every Year, and all the Ships from that Size to be covered once in 18 Months; also that every one of them shall be calked and dress'd above the Waters Edge every Year, and then the Quantity of Pitch to dress such a Number of Ships as there is in the Publick Service, according to the Method prescribed will be as follows.
|First||1700||Magnitude of the Ship.||18||Number of Barrels of Pitch that will dress each Size.||12||Number of Barrels of Pitch that will be expended every Year for one Ship of a Sort.||7||Number of Shipo there is of each Size.||84||Number of Barrels of Pitch that will be expended each Year to dress all the Ships.|
Memorandum, That there being 30 Fireships, and they being equal to the fifth Rates, the Number of Barrels of Picth to dress them will be 165.
Then for Yatchs, Bomb-Vessels and Scout Boats, they being 34 in all, (and I allow them equal to sixth Rates) the Number of Barrels of Pitch will be for them 93, added to 165, is 258, and adding in 1358, the Total Sum will be 1616.
Then the Number of Barrels of Pitch to dress a Ship of each Size every Year, will be 45 and a half, and the whole Quantity for doing it every Year will be 1616 Barrels of Pitch; then the Quantity of Pitch, which very probably is expended every Year on the Publick Ships, with what is used on Boats, Carpenter's Sea-Stores, and the ordinary Services of the Navy, as the Yard's Expence; also for pitching Planks within-side under Water in new built Ships, then for Timber-Hoys, Transports, Lighters, and the like, may be reasonably be 500 Barrels more, all which amounts to 2116 Barrels, which at 40 s. a Barrel, is 4232 l. a Year for Pitch, to which I shall subjoin the Charge of the Tar as follows.
The Use of Tar is more various than the Pitch, since at some times they mix Tar with Pitch, to Pay Ships Bottoms under Water, believing the Pitch by itself will be too hard, and will not penetrate into the Pores of the Plank, for which Reason they ought to make the Plank very hot, when the Pitch is applied, also the Tar ought to be full hot, and also clear of Dross.
However, as to the Tar, which is put amongst Pitch to soften it, I have allowed it already, and therefore have nothing to consider of but the Tar which will be requisite to pay the Ship's Sides and Deck, which I shall set down as follows.
|First||1700||Size and Magnitude of the Ship.||5½||Barrels of Tar requisite for one Ships of a Size.||7||The Number of Ships there is of each Size.||35||The Number of Barrels of Tar which is expended every Year on the Ships mention'd.|
The Fireships are thirty, which I will allow equal to a fifth sized Ship, so the Barrels of Tar for them will be
Then for the Yatchs, Bomb-Vessels and Scout-Boats
Carpenter's and Boatswain's Stores in one Year may be
For the Yards Use, and Transports, Ligthers and Hoys
Then the Total Sum of Tar expended in one Year, will be 1339 Barrels, at 1 l. 6 s. 3 d. a Barrel, is 1722 l. which put to 4232 l. the Value of the Pitch, it makes 5954 l.
Now it's very probable that there may be twice such a Quantity of Pitch and Tar expended throughout our Kingdom in private Affairs, so that the Sum to purchase it will be 17862 l. every Year, and such Commodities being generally obtain'd with Bullion, it is so much the worse for us; for could it be purchased for Goods of our own Growth, it would be little otherwise than Barter, to the Encouragement of our Manufactures, as well as to the Exncouragement of Strangers.
Whether my Computation on this Head is over or under the real Quantity of such Goods that is yearly imported into these Kingdoms, it matters not; I shall therefore refer the nice Account and Knowledge of what is brought over to those that are placed purely to take Account, and only make these Intimations, to shew what might be advanced in his Majesty's Dominions, and that our Countrymen may not be streightened for the want of such Goods, if the Fereigners should hinder our Traffick: And so I suspend this Discourse, believing that I have laid down all the Rules, (or indeed what is most material) in Calking any Ship, also in paying, slubing, or dirting of her with Pitch, Tar, and the like, which I presume in most Ships are scraped off again, except that which lyes in the Seams to cover the Oakham; and after such cleansing, it's general for new Ships to be adorn'd and beautify'd with Paint. To which particular Consideration I shall proceed and consider of it in the next Place.
Transcribed by Lars Bruzelius.
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