Chymical Vessel then let all be beaten and well brayed 24. hours and then in the end reduce it into very fine small grains A Liquor for this purpose may likewise be made of twenty parts of Aquavitae and 12 parts of distilled Vinegar made of Whitewine and four parts of Spirit of Salt-Peter and two parts of water of Sal-armoniac and one part of Camphire dissolved in Brandy-wine or reduced into Powder with powdered Sulphur or reduced with Oyl of sweet Almonds To Corn Powder well you must prepare a Sieve with a bottom of thick Parchment made full of round holes then moisten the Powder that must be corned with its water and make it up in Balls as big as Eggs which put into the Sieve and with it put a wooden Bowls and when you have so done sift the Powder so as the Bowl rouling about the Sieve may break the Clods of Powder and make it pass through those little holes into Corns It is observed by Fire-Masters and Gunners that Powder when it is Corned is of much greater force and power than in Meal from hence 't is concluded that powder when 't is put into a Piece of Ordnance ought not to be pressed or beaten home too hard in the Piece for thereby it will loose its form of grains and thereby looseth a great part of its strength that it had and is therefore not able to throw out the Bullet with so great a violence as if the Powder had been gently thrust home to the Britchend CHAP. XVIII Of the several Colours which are to be given to Powder KNow first that all the blackness which you see in Gun-powder comes from the Coal not that this colour is absolutely necessary to be conjoyned to its nature or that it is absolutely necessary to be given to it for its meliorating or making it more vigorous this is not so but by contraryes you may be permitted to give unto it any such colours as you shall think fit without prejudice or hinderance of the Powder and vertue of it For if instead of Coal you take rotten dryed wood or Sawdust well dryed or white paper moistned and dryed in a Stove and powdered or indeed any other thing of a combustible nature or that is well disposed to take fire such as you read hereunder and to this you may add a colour according to your fancie and pleasure and you will infallibly have a Powder that will make the same Effect as the black powder And for this purpose I shall lay down in this Chapter certain mictions with which I served my self many times and therefore known to be experimental truths White Powder Take Salt-Peter six pounds Sulphur one pound of Sawdust of the Elder Tree well dryed and powdered one pound these mixed according to the directions in the former Chapter there will be made a Powder of a white colour Or thus Take Salt-Peter ten pounds of Sulphur one pound of the woody part when the Hemp is taken away one pound c. Or thus Salt-Peter six pounds Sulphur one pound of Tartar calcin'd until it be brought to a whiteness and the Salt extracted for use one Ounce Red Powder Take of Salt-Peter twelve Parts of Sulphur two parts of Amber one part of Red Sanders two parts c. Or Take Salt-Peter eight pounds of Sulphur one pound of dryed powdered Paper boyled up in a Water wherein is Cinaber or Brazil Wood and then again dryed one pound Yellow Powder Take Salt-Peter eight pounds Sulphur one pound Wild or Bastard Saffron boyled in Aqua Vitae after dryed and powdered two pounds c. Green Powder Salt-Peter ten pounds of Sulphur one pound dryed Wood or Saw-dust boyled in Aqua Vitae with some Verditer then dryed and powdered of this two pounds Blew Powder Salt-Peter eight pounds of Sulphur one pound of the Saw-dust of the Teil Wood boyled in Brandy Wine with Indigo and after dryed and powdered one pound CHAP. XIX Still Powder or Powder without Noise THere are several that do Write many strange things concerning this Still Powder or Powder without noise or as some do give it the name Deaf Powder whereof they have treated prolixly the which I think not convenient to do by reason I am loath to tire the Reader with any such Discourse as tends not much to Edification I shall therefore put down certain mixtures which I have known to be more excellent and best approved First way Take Common Powder two pounds Venus Borax one pound these being well powdered mingled and incorporated together must be made up into Corn Powder Second way Take common Powder two pounds Venus Borax one pound of Lapis Calaminaris half a pound of Sal-armoniack half a pound powder and mix them well and make them up into Grains Third way Take common Powder six pounds of Live Moles burnt in an Earthen Pot of Venus Borax half a pound mix them as before c. Fourth way Take Salt-Peter six pounds Sulphur eight pounds and a half powder of the Second Bark of Elder Tree half a pound common decripitated Salt two pounds make Corn Powder of these according to the precedent order or accustomed method To these known things I shall add here a thing whereof you may make experience if you please it being only taken from the Books of Authors without any tryal made by me which you may also find written in the natural Magick of John Baptistâ— Porta which is in our English Tongue where he saith that if you add burnt Paper in the Composition of Gun-Powder or the double quantity of Hay seed well beaten these will take away a great part of the strength and will hinder it from making so great flame and noise Some do say that the Gall of a Pike doth the same effect if it be mixed and mingled with the same but we shall leave the belief of these things to the faith of such Authors as have experimented the same There are some wise and knowing men in this Art attribute the cause of this noise or as some do express it this horrible noise produced by a Cannon after the firing not to the Powder but to the beating and contusion of the Air which is inraged or in a passion by being so furiously endeavoured to be stifled or choaked by a strange and extraordinary movement of which we have spoken more at large in the former Chapter where we treated of Salt-Peter Yet in favour of the Sons of Art we shall never theless give you the opinion of Scaliger taken out of his his fifteenth Book in his Exer. Exoter against Cardan of Subâ—il Exer. 25. Loâ—ge pâ—jus illud cum sonitus causam a bellicis machinis editi attribuis Sal Petrae nanâ— tâ—nuissimuâ—n in pulverem comminuâ—um cavernulas amisit CHAP. XX. The Proof or Tryal of Gun-powder IT is accustomary for men skilled in these Arts to try Powder three several wayes that is by sight by touch and by fire And first for the tryal by sight it
How to prepare Match or Low for Artificial Fires MAke Cords of Tow Hemp or Cotton which you please of two or three twists not made too hard put them in a new Earthen pot Vernished pour upon them Vinegar made of good white Wine four parts of Urine two parts of Aqua vitae one part of Salt Peter purified one part of Cannon Powder reduced to Meal one part Make all these Ingredients boyl together upon a great Fire to the Consumption of all the Liquor then spread upon a great smooth Plank or Board the Meal or Flower of the most excellentest Powder that you can get Having drawn your Match out of the Pot roul them in the Powder and then dry them in the shade or Sun for it matters not which and the Cords or Match that are thus prepared will burn very quick Francis Jouchim Prechtelin in his second part of his Fire-works Chap. 2. describes a certain Match which is extream slow in burning and is thus made take Mastich two parts Colophonia one part Wax one part Salt-Peter two parts Charcoal half a part then having melted all and mixed them well upon the fire take a Match made of Hemp or Flax of a sufficient bigness and draw it through this Composition making it go down to the bottom of the Vessel drawing it often through until it hath gotten the bigness of a Candle and when you desire to use it light it first and when it is well lighted blow it out and there remains none but a burning Coal CHAP. VIII Of certain Antidotes excellent and approved against the burning of Gun-powder Sulphur hot Iron melted Lead and other like accidents drawn from the particular Experiments of Cozimu Nowicz SECTION I. BOyle Hogs grease in common water over a most gentle fire the space of some time then take it from the Fire and let it cool and after expose it to the fair and clear weather three or four nights after having put it into an Earthen pot melt it again upon a small fire and being melted strain it through a Cloath into cold water after wash it many times with good clean and fresh water until it come as white as snow this done put it into a glazed pot to serve you at your occasions The use is thus you must annoint the burnt part as soon as you can and you will see a quick and admirable effect SECT II. Take Plaintain water Oyl of Nuts of Italy of each as much as you please SECT III. Take Mallows water Rose water Plume Allum of each as much as is necessary and mix them well together with the white of an Egg. SECT IV. Take a Lixivium made of Calx Vive and common water add to it a little Oyl of Hempseed Oyl Olive and some whites of Eggs mingle all well together and annoint the burnt place with this Composition All these Oyntments cure burnings without causing any pain These I have often experimented upon my self Some Receipts from divers Authors Take Oyl of Olives Oyl of sweet Almonds Liquid Vernish each one part juice of Onions two parts with these chafe the part affected If there be already blisters raised and Ulcerations in the parts this following Oyntment is most excellent Boyle a great quantity of the second Rind of Elder tree in Oyl of Olive then pour it through a Linnen cloath add to it a little after two parts of Cerus or burnt Lead of Lytharge of Gold of each one part put them into a Leaden Morter and then stir them about and mix them so that they become in the form of a Linament Take melted Lard pour it into two Ounces of Morrel water and one Ounce of Oyle of Saturn then mingle them well together ' this Remedy is soeveraign Take the Mucilage of the Roots of Henbane and of the Flowers of Poppies of each one Ounce Salt Peter one Ounce mingle them all with Oyl of Camphire and make a Linament according to Art Or take the juyce of Oynions rosted in embers two Ounces Nut Oyle one Ounce mingle them all well together Or take of the Leaves of Ivy two m. or handfuls well beaten up with Plaintain water Oyl Olive one pound make all boyl with four Ounces of good white Wine until the Consumption of the whole Wine at the end of the decoction add Wax as much as is necessary to give him the form and consistency of a Linament Again take old Lard let it be melted over the flame and poured into two Ounces of the juyce of Beets and Rue of the Cream of Milk one Ounce Mucilage of Quince-seeds and Gum Tracanth of each an Ounce and a half mix them well together and make thereof a Linament This remedy is none of the worst we took it from Joseph Quercetanus in libro Sclopetrio CHAP. IX Of Hand Granadoes THe Hand Granadoes respecting their form are Globically or perfectly round and hollow in their interior part in manner of a Sphere they are called Hand Granadoes or Handy Granadoes because they may be grasped in the hand and thrown to the Enemies and if we should dwell upon the denominations of the Latine we may call them as they do Granades Palmares they are commonly of the bigness of a Bullet of Iron of 5 6 and 8 l. they weigh sometimes 1 l. and sometimes one pound and a half some are of two pounds and others of three pounds there is given to these sort of Globes the names of Granadoes by reason of the great resemblance they have with the Fruit Punique which we call Pom-granad for as these do shut up in their rinds a great quantity of grains so our Military Globes are filled with a number of Grains of Powder almost innumerable the which having received the Fire do break into a thousand and a thousand shivers leaping against the Enemy and piercing if it could all such things as it meets opposing its violence They are generally made of Iron or Copper carrying in its Diameter about three Ounces being about the length of a Barly Corn in thickness of Metal they are filled commonly with Gun-Powder and sometimes of other Compositions there is added to its Orifice a small Pipe commonly called a Fuse which is filled with a matter or Composition that is slack or slow in burning but nevertheless very susceptible of the Fire and capable to hold fire some time for fear that it should break in the hands of those that mannage it and intend to throw it There is amongst Fire-Masters accounted three sorts of Hand Granadoes the first and most common are made of Iron others are made of Brass allayed with other Metals in the melting the third sort is of Glass If you cause them to be made of Iron take such as is most fragile and as little wrought as possible you can get if you will cast them of Copper you must allay six pound of Copper with two pounds of Tyn and half a pound of Marcasite or you may put one part of Tyn with
half a pound of Sal-armoniac 4 ounces Above all this the Chymists know how to prepare a certain oyl of Sulphur which they call a Balsam of which the virtues are so admirable that they admit not any body either living or dead to be touched with putrification but will conserve it in so perfect and entire state that neither the pernicious Influences of the celestial bodies nor that corruption which the Elements produce nor that which reduces things into their Principles can any way damnifie it if anoynted with it There is also from it prepared a certain fire as Tritemius teacheth with flowers of Sulphur Borax and Brandy-wine which will remain many years without extinguishing of it self Others that are knowing do attest that a Lamp may be filled with such like Oyl from whence all that are within the Light of it will appear as if they had no heads There is another way of making Oyl of Sulphur which is very admirable and excellent which is prepared thus Incorporate well together an equal proportion of Sulphur and Salt-Peter reduce them into most subtile Powder and pass it through a fine sieve then put them into an Earthen Pot that hath never been used and pour upon them Vinegar made of White-wine or Aqua-vitae as much as will cover the Powder Close the Pot in such manner that no air may any wise enter and put it thus in any hot place so long time until all the vinegar be digested and vanished Lastly take that matter which rests in the Pot and draw from thence an oyl by Chymical Instruments proper to this work CHAP. II. The preparation of the Flowers of Benjamin TAke Benjamin a certain quantity of ounces put it into a Gourd or a Limbeck glass and close it well with a blind head as they call it then have in readiness an earthen vessel set it upon a Tresfoot or for the more certainty upon a small Furnace place it in your glass body and compass it well about with fine Sand or ashes so high as the matter is in the glass after make a moderate fire under it for fear the Limbeck heat too soon and be too hot for that will make the flowers become citrine or yellow when they ought to be as white as Snow Observe when you see the flowers begin to raise a vapour or small fume continue your fire in that same degree the space of one quarter of an hour after you shall see the flowers risen unto the internal Superficies of the blind head then take it away carefully and put to it another that shall be quite cold and put that which you have taken off upon a white paper until it be cold then gently with a Feather or wooden Spatula cause the flowers to come forth of the blind head and gather them together carefully thus you may add a third or fourth blind head and in time many until all the Benjamin cease to fume Benjamin may be made into flowers another way thus put into a glazed pot a certain quantity of ounces of Benjamin and place it upon warm ashes and when you see it begin to fume cover the vessel with a Cornet of paper made in the form of a Cone and a little larger than the orifice of the pot leave it there about one quarter of an hour after take off the Cornet and take the flowers and gather them together then put upon the vessel another Cornet of paper and let it stand as long as before take it off and gather the flowers to the former and continue thus putting Cornet after Cornet until your flowers be entirely evaporated CHAP. III. The preparation of Camphire TAke Juniper Gumm which is called somtimes Sandarach white varnish or Mastick most subtilly powdered 2 l. white distilled vinegar as much as is necessary to cover the Gumm in a glass set it deep in horse-dung the space of 20 days then take it and pour it forth into another glass Vessel with a wide mouth and let it stand thus in digestion a whole moneth and in it you shall have Camphire congealed in form of a Crust of bread and which hath in some measure the resemblance of the verâ—able or true Camphire The Camphire hath such a love for the fire that being once lighted it goeth not out until it be quite consumed The flame that comes from thence is very clear and of a very agreeable odour after it hath remained suspended in the air some time it vanisheth insensibly The cause that produceth all these rare effects from Camphire is by reason its parts are extream subtil and airy I do add to all this that it may be easie to reduce Camphire into Powder to make it useful in artificial fireworks if a man crumbles it and beats it gently rouling it with Sulphur The oyl of Camphire which serves also for the same effect is made by adding a little of oyl of sweet Almonds and stir them well together in a brass Morter and pestle of the same metal until all be converted into oyl of a greenish colour Or a man may put it into a Glass Viol which must be close stopped provided also that the Camphire be true and natural and not a Cheat then put that Glass into a warm Furnace and draw it out when you shall see all the Camphire turned into a pure clear oyl which will burn with an admirable vivacity CHAP. IV. Water of Sal-armoniac TAke Sal-armoniac 3 ounces Salt-Peter 1 ounce reduce them into a most subtil Powder and mix them well together after put them into a Limbeck and then pouring on them some of the best and strongest Vinegar you may distil the same into a water with a small fire CHAP. V. Of a certain artificial water which will burn upon the Palm of your hand without doing any harm TAke Oleum Petroli and of Terebinthi and of Calx vive of Mutton fat and of Hogs Lard of each equal parts beat them well together until they be well incorporated then cause them to be distilled in warm ashes or upon burning coals and you shall draw from thence an excellent oyl CHAP. VI. To prepare Fire-Spunges TAke of the oldest and greatest Toad-stools which grows at the Root of Ash Oak Birch and Fir-tree with many other Trees which produce them freely get a good parcel string them and hang them in the Chimney and leave them to macerate being well mortified and macerated take and cut them in pieces and then beat them with a wooden Mallet this done boyl them over a small fire in a strong Lye and a sufficient quantity of Salt-Peter until all the humidity be evaporated At last having put them upon a Plank or even board put them in a warm Oven and let them well dry there having drawn them from thence you must beat them with a wooden Mallet as before until it become wholly subtile and soft being thus prepared you must keep them in a commodious place to serve you upon occasion CHAP. VII
reasonable to pass into the Air and to elevate it self on high without any difficulty and in such a sort that those bundles may not by any means give hinderance or stoppage to their rising in a streight line and take care most exactly that the Fuzee be not so big but that they may retain as near as you can a Pyramidal or Conical form when all its weight that may be is adjoyned to it 20. Men ought to shun as much as possible those nights that are rainy moist and when the Sky is darkned with black clouds as being very incommodious and offensive to the Fuzees And more than that avoid impetuous Stormy winds and the Whirl-winds hinder no less than the first 21. You may not reject above other causes the different effects which are produced by sundry Fuzees although they be charged with one and the same Composition no otherwise than thus that they were not made with an equal diligence either in the Charging or Peircing or in the other Circumstances which you were obliged to observe or in this that it may be some may have been kept in a more moister place than the others where they have acquired too much moisture which causeth to them effects much different one from another as well in Rising as in Consuming 22. If you would make appear in the Air streams of fire or a quantity of burning sparks or stars or long large rayes to dart from the Fuzees there is accustomed to mix with the Composition some small quantity of powdered Glass grosly beaten filings of Iron Sawdust One may also represent fire of divers colours as we have shewed before in the fifth Chapter but more particularly thus if you put a certain portion of Camphire in your Composition you will see in the Air a certain fire which will appear white pale and of the colour of Milk if you put Greek Pitch which is a light yellow Pitch used in Plaisters called Pix Burgundy it will represent unto you a red flame and of the colour of Brass if you put in Sulphur the fire will appear blew if Sal-Armoniack the fire will appear Greenish if from Crude Antimony the flame will be Red Yellowish and of the Colour of Honey if the filings of Ivory be added they will render a Silver-like White and shining flame yet something inclining to a Livid Plumbous colour if the powder of Yellow Amber be added the fire will appear of the same colour with the Citrine lastly if black Pitch be added it will throw forth an obscure smoaky fire or rather a smoak that is black and thick which will darken all the Air. CHAP. XIV Of Odoriferous Aquatick Balls CAuse to be made by a Turner Balls of wood hollow within about the bigness of a Wild Apple which you must fill with some one of these Compositions hereunto annexed and they being all prepared and charged you may throw them into the water after they are lighted but it ought to be done in a Chamber or close place that the fume may be the better kept together and this must be done with some small end of our Match made of prepared Flax or Hemp to the end that the Composition which is shut up in the Globe may take fire with the greater facility The Compositions are these that follow viz. Take Salt-Peter Storax Calamite one Dram Incense one ounce Mastick one ounce Amber half an ounce Civet half an ounce of the Sawings of Juniper wood two ounces of the Sawings of Cypress wood two ounces Oyl of Spike one ounce Make your Composition according to the Art and Method given Or Take of Salt-Peter two ounces of Flower of Brimstone Camphire half an ounce powder of yellow Amber half an ounce Coals of the Teile tree one ounce Flower of Benjamin or Assa sweet half an ounce Let the matters that may be beaten be powdered afterwards well mingled and incorporated together CHAP. XV. Compositions to Charge Globes or Balls that will burn as well under as above water FIrst take Salt-Peter reduced into fine meal 16 l. Sulphur 4 l. of the sawings of wood which hath been first boyled in a Nitrous water and afterwards well dryed 4 l. Of good Corned powder half a pound of the powder of Ivory 4 ounces Or thus Salt-Peter 6 l. Sulphur 3 l. of beaten powder 1 l. Filings of Iron 2 l. of Burgundy pitch half a pound Or thus Salt-Peter 24 l. of beaten powder 4 l. Sulphur 12 l. of Sawdust 8 l. of yellow Amber half a pound of Glass beaten in gross powder half a pound of Camphire half a pound For that which concerns the manner of preparing all these Compositions it differs nothing from what we have prescribed in the making of Rockets only 't is not necessary that the materials be so subtilly beaten powdered nor sifted as for those Fuzees but nevertheless to be well mixed one among another Care must be taken that they be not too dry when you charge the Globes or Balls and for that purpose they may be moistned with Linseed-oyl Oyl of Olives Petrole Hemp-seed Nuts or any other fatty humour that is receptible of fire Note that amongst all these Compositions of matters that will burn in the water which I have here proposed from my own particular experience every one may make them as pleaseth himself best provided he always take the materials in proportion one to the other as they ought But nevertheless I shall counsel you to experience from time to time your Compositions for the greater surety before you expose them to the publick view of the world It is also amongst the rest very necessary that you learn the force and strength of every material you put into the Compositions whereby you may at your pleasure know how to alter and vary your proportion as you shall judg fit CHAP. XVI Of Stars and fiery Sparks called by the Germans Stern-veuer and Veuerputzen I Have shewed the Composition of Stars in Chap. 5. I have also shewed the way of making them up and their use and also I have shewed the manner of giving to them various Colours as in the 22 Rule of the 13 Chapter where I had an intent to say no more of these things But finding in Master Cazimier's Artillery these Compositions which I judge may prove very excellent therefore I thought good to insert them that I might leave out nothing that might make more perfect any thing we treat of First you must know that between fiery Sparks and Stars there is this difference that the Stars are greater and are not so soon consumed by the fire as the Sparks are but do subsist longer in the Air and do shine with greater substance and with such a light that by reason of their great splendor they are in some manner comparable with the Stars in the Heavens They are prepared according to the following Method Take Salt-Peter half a pound Sulphur two ounces Yellow Amber powdered one Dram Antimony Crude one Dram
of beaten Powder three Drams Or Take Sulphur two ounces and a half Salt-Peter four ounces Powder subtilly powdered four ounces Olibanum Mastick Christal Mercury sublimate of each four ounces White Amber one ounce Camphire one ounce Antimony and Orpiment half an ounce All these materials being well beaten and well sifted they must be mixt together with a little Glue or gum-Gum-water made with Gum-Arabick or Tragacant then make them into small Balls about the bigness of a Bean or small Nut which being dryed in the Sun or in a Pan by the fire may be kept in a convenient place for such uses as we have spoken of in the fifth Chapter of this Book You must only remember that when you would put them into Rockets or Recreative Balls they must be covered on all sides with prepared Tow of which we have shewed the way of preparing in the seventh Chapter of the first Part of our Fire-works Sometimes Fire-Masters are accustomed to take in the places of these little Balls a certain proportion of melted matters of which we have spoken in the first Part of Fire-works But if these do not please you by reason of their swarthy colour but you rather desire to see them yellow or inclining somewhat to white then take of Gum-Arabick or Tragacant four ounces powder it and pass it through a Sieve of Camphire dissolved in Aqua-vitae two ounces Salt-Peter a pound and a half Sulphur half a pound Glass grossy powdered four ounces White Amber an ounce and a half Orpiment two ounces make all these Ingredients into one mass and make Globes of them as before I Learned this saith my Author from Claude Midorge For the method of making Sparkles in particular it is thus Take Salt-Peter one ounce of this Liquid matter half an ounce of beaten Powder half an ounce of Camphire two ounces after you have beaten all these materials into powder every one by it self put all of them into an Earthen Pan and put upon them the Water of Gum Tragacanth or Brandy-wine wherein you have dissolved some Gum Tragacanth or Arabick until it be of a good consistency that done take an ounce of Lint which has first been boyled in Brandy-wine or Vinegar or in Salt-Peter and after dryed again and the threads drawn out then put it into the Composition and mix them well together so well and so long until it has drank up all the matter of these Compositions make little Balls in the form of Pills and of the bigness of great Peas which you must roul in mealed Gun-powder and dry them whereof you may serve your self according to the method we have prescribed Besides these there are certain odoriferous Pills prepared which are employed in small Engines and fiery Inventions which are shewed in Chamber Roams or close Cabinets these are commonly prepared of Storax Calamite Benjamin Amber white and yellow and of Camphire of each one ounce Salt-Peter three ounces of Coals made of the Teil Tree four ounces beat all these Ingredients to powder then incorporate them well together and moisten them with Rose Water in which is dissolved Gum-Arabick or Tragacanth to make thereof little Balls at last having fashioned them expose them to the Sun or to the fire to dry THE DOCTRINE OF PROJECTS APPLYED TO GUNNERY By those late famous Italian Authors GALILAEUS AND TORRICELLIO Now rendred in ENGLISH LONDON Printed in the Year 1672. THE PREFACE GALILAEUS in his 4th Dialogue of Motion hath largely treated of aequable and accelerate or increasing Motions as also of that of Projects or things shot and thence derived several Propositions or Conclusions and hath likewise made several Tables touching the Amplitudes or Base Lines and the Altitudes or Heights of the Semiparabola's or Curves described by the Motion and Ranges of Projects The which Doctrine the late Famous Torricellio of Florence having with great Judgment much advanced and facilitated applying the whole to the Art of Gunnery that the benefit of his pains might redound to the English Reader that is especially Delighted or Exercised in the Affairs of Mars it was thought fit to render the same into English THE DOCTRINE OF PROJECTS APPLYED TO GUNNERY PROPOSITION The Impetus B A that is as much as is that of the moveable naturally falling from B to A by the * Which Definition is when we name an Impetus given we determine it in spaces according as Galilaus useth Exemp Grat. When we say let the Impetus given be A B then we mean let the Impetus given be so much as is requisite to throw the Project from A to the highest point of the perpendicular B or which is the same as much as is the Impetus of a moveable naturally falling from B to A. Definition as also the Direction A I according to which the Projection is to be made with the said Impetus being given it is required to find the Amplitude Altitude and the whole future Parabola of this Projection Again I say that this Parabola is described by the Impetus given for AE EF and EB or those three lines equal to DG the Altitude GF the Semi-base and GL are in continual proportion Wherefore GL is the sublimity by the V. Proposition De metu Projectorum of Galiaeus and its Corollary Then thus the Impetus of the Parabola AG in the point A is as much as that of the Cadent naturally falling from L to D by X. of Galiaeus that is from B to A or of the Project ascending from A to B therefore the Parabola hath in the point A the Impetus that was given wherefore that is done which was required But because this Proposition is of great moment for clearing of those that follow we will prove it another way First it is manifest that the point P cannot be in the line LD because since the line AC toucheth each Parabola that ID the common Axis should be cut into two equal parts in two points by the Vertex's of the Parabola is absurd Nor can it be in the line EG for drawing the Diameter suppose MN thorough the â—â—rtex that MN should be cut into two equal parts by the line EG is absurd for only ID of all the lines parallel unto it in the angle CAD can be cut into two equal parts Now let the point P fall any where at pleasure and draw the Horizontal line PR for as much as PN and PM are equal by the II of * this NR and RA PR and RS Which second Proposition is that the sublime point of the Range of any Project P doth cut the Perpendicular M intercepted betwixt the Horizon and line of direction into two equal parts shall be equal And because the Parabola AP hath the Impetus BA that is OM the Point O shall be its sublimity and for that reason the lines OP PR and PM shall be in continual proportion and the Rectangle OPM equal unto the square PR and changing the lines