¶ An apology confirmation explanation and Addition to the Vranicall Astrolabe by the Author.  
FIrst for apology and Confirmation of the thing I do not see but I may well (without flattering or overmuch affecting my own doings avouch it to be the best & rarest devise for an Astrolabe that ever came forth in any age, & to most use & pleasure, and do wish any man that thinketh he can contradict it to do it in writing that I may either yield or answer. For, to backbite or detract by words any man that hath openly published himself by writing is neither honest nor credible, rather it bewrayeth himself to be either partial, malicious, ignorant, or vainglorious. But to the matter I say for an Astrolabe not comparing it (though the devise be more new & rare) with the Catholicon or jewel, which containeth in it the several uses, not only of all Astrolabes but also of the Sphere and Globes themselves, and of all other Instruments both Astronomical and Geometrical, being fitted accordingly as hereafter if God permit I will yet more manifest. Therefore very unaptly by Gemma Frisius named Astrolabum Catholicon had he not added thereunto in his title. In quo quicquid uspiam rerum mathematicarum tradi possit continetur etc. And for that cause I having amplified the devise both in fashion & use, named it the Mathematical jewel But to fetsorth an Astrolabe: and no more but an Astrolabe: then I say, that this and no other is Astrolabium Catholicon or Generale. Which must needs be confessed, if with Messahala we do but define the word Astrolabe who (as Io. Stophlerus reporteth) saith, that Astrolabium est nomen grecum cuius Interpretatio est acceptio stellarun. In latin it is called (as Stophler saith) Astrolat sus: quasi astrorum casus vel lapsus, vel quia metitur lapsus vel transitus astrorumet signorum. Wherefore seeing it appeareth by the definition of the name: that the very Intendment of the devise of the Astrolabe, was but to comprehend the lapses, courses, rise, and settings of the signs, stars, and planets, unto the sundry Orisons in several countries and latitudes: and no further. All which this my Vranicall Astrolabe so effectually, so plausibly, so pleasingly, so easily, and so sufficiently performeth. That (the round globe itself excepted) neither he jewel, neither any other devise of Astrolabe either general or particular, of which many have been, and with great joy and applausure heretofore received, cometh any way near it. Therefore I can not see how or with what face any man can justly detract from it. Let me here examine the matter publicquely, and to make short & come speedily to the point omitting such horoscopes as Apian & others published with their cylinders ships, rings & many other learned Ludicra & devices in dial's framed for the rising and setting of the signs & stars, and leaving out such Astrolabes as old Sconer and divers other did set forth which wear never much accounted of, and strait jump in with that high commended and so ever well accepted Astrolabe, even the very foundation of all that have been since which Io. Stophlerus last established in his book de Fabrica et usu Astrolabijs. even that Astrolabe without which on the backside, Gemma Frisius would not allow his Catholicon currant: although in my jewel I supply it on the face, and that more general. Well then, if you thoroughly consider of, or look into that so excellent devise: whether to a particular Horizon as Io. Stophlerus framed him: or general to all Orisons as G. Frisius appointed him: or more general to all Orisons & both Poles, as myself in my jewel devised him: yet by all those devices, in regard that of a 1000 starts & upwards well known & recorded by Images in the heavens conceived, there could be no use of above 40. or 50. of them. & that use half purblind for want of the Images. And that in this Vranicall Astrolabe there is equal use of the whole trope & of every Image & constellation in his full proportion, as plain as the day to be feene: a few towards the South pole which with us are never seen excepted: and that many more astrolabical propositiones are to be performed thereon, general to all Orisons, than before could be done by that of Stophlers to one Horizon. Therefore I can not but most confidently defend, confirm, and prefer the devise thereof before them all in his kind. And adding another face thereunto, for those few constellations wanting & considering the small charge, the easy portabillity & the readiness of 〈◊〉 (for which 3. causes the Astrolabe was first devised & ever accounted of) it might seem a devise now sprung up to put down the globe itself. Add to these my new devise of the Horarlum Planetarium on the top thereof, many ways before attempted, yet never made general before: also the devise in the two side semicircles (where once I had thought to have placed the said south constellations wanting) for equating & rectifiing of the fixed stars, for all ages, past and to come: never joined to any other Astrolabe. These I hope may satisfy for an Appollogie & confirmation of the devise: if not: Sure I am, they may make you look a Term or two longer for my Organum Vranicum than I promised, because I mean once again to peruse & write over the copy perceiving by this that the Incorporating of th'histories with the precepts, which I used here and thought hereafter more to use for brevity of writing, will make the more prolixity of understanding for young practisers. Unto whom, my harsh lose & deliver of that I conceive, (nature affording me no better) I perceive is of itself hard enough: which as I am sorry for, so have I been always willing, as I have still offered & that gratis, viva voce to remedy it, as divers by experience can testify.  
THen for Addition to the parts of this Astrolabe, let the Mater or Celestial thereof remain as at the first, only I think good in steed of the letters I F.M.A etc., for more readiness to write the words januarie, February, March etc. unto the same places of the Ecliptic circle whereas the Son entereth the 12. Months of the year.  
Let the Zenitfer also remain as before saving that, I would not have the howercircle thereon described, neither any numbers wtitten in capital letters, because they are cumbersome, but in steed of them smaller figures set upright the standing way as in this figure of the Almcantifer you see done from 50. to 70. and those are needful, but in the Noon line for the double numbering from the centre out-wards, but in the North line there need not any such.  
Let the Cursor now carry one quadrant of 90 deg. feruing chiefly for the Azimuthes, and therefore called the Azimuthall quadrant, numbered double uz. upwards and downwards, and another of 6. hours double numbered also: but upwards, all one way, called the hour quadrant: all which by his figure marked with A B C D. you may here see whose line A D is his fiducyall line which must always run very square cross the Zenitfer as in the 1. Chap. is showed, his line A B keeping in that motion even with the fiducyall line of the Zenitfer, at whose point A must be a centre loop hole for the Almicantifer to play upon. And at B let be another centre loop hole with a loop of thread, or a hook always fixed therein to hitch a thread and pearl unto, when need requireth.  
Also I would now have even for ease as much as for use three narrow Cursors O P & Q which may be called lydgers rather than Cursors, to be planted for all questions of one latit. even fixed on the Zenitfer: the one at the vertical point in the Noonelyne, the other at the Horozontall point in the North line, the other at the Azimuthall point in the North line also, which point is always twice so many radiall degrees from the centre as the latitude of your place amounteth unto and was not mentioned any where in the Book: and the Vertical and Azimuthall lydgers to have each a centre loon hole to hitch a thread and pearl unto, when cause requireth.  
NOw to the Explanation which methinks should not need any until past the first 12 chapters because those contain nothing but what is common in every Astrolabe in a manner: most easy to be understood of any that hath read but the first principles of the globe or spear. For all the Eccentric circles of the Mater, uz. such as are not described on the centre of the Celestial or Mater of the Astolabe, are no other (as in the 2 cap. is said) but thecliptic circle of the Zodiac marked with BC, with every fift of his circles of longitude, distinguishing the whole face into the 12 signs & their parts, issuing from his poles: and every fift of his parallel circles of latitude, passing on each side towards each of his poles, or so many & so much of them as the proiectment would allow, which admitteth but one of the Zodiacs poles within it marked with the letter D. And thereon is only the Aequinost. circle described concentric cutting thecliptic at the beginnings of Aries & Libra at B & C, whose numbers & devifions because they should not disturb the Mater, are set in the outer limb thereof: where note that B standeth at the tip of the tail of Cetus, C. in the right wing of Virgo, D under the foot of Draco though some hath said there be no such letters. And now, who can not easily by the squares made with the cross of those circles of long. & latit. easily descry the longitudes & latitudes of any star, carect, or constellation thereon set or drawn as in the 2 cap. is taught. And seeing the centre of the Astrolabe marked with A, representeth the north pole of the world about which the Zenitfer moveth. The radiall degrees of whose nooneline are numbered from thequinoctials intersection, where the ✚ standerh either way towards each pole. Who can be so ignorant but to know that by the leading about thereof by the degrees of the Matters limb, that his fiducyall or nooneline may show the 360 Meridian's of the globe, though to avoid confusion of lines they be not drawn on the Astrolabe, & that his radial degrees do limit out the parallels of latitude or declination from thequinoctial by that leading about.  
But to come unto the residue of the book wherein our new devised tackling is applied to so excellent uses general to all Orisons: which as it seemeth hath more want of Explanation. The first thing you have now to do when any question is proposed, is to set the Index of the hour circle unto the place of the ☉, for the day or time of your question by help of the 5 cap. the & noneline, that is to say bring the nooneline of the Zenitfer unto the degree of thecliptic answering your day proposed, and then apply the Index of the howercircle even therewith, so is the hour circled planted for that day, and in like sort you shall from day to day by help of the nooneline remove the Index further & further for every day a degree rebating the odd minutes in the 5 cap. mentioned. So shall the nooneline now show you still thereon the hour in every question unasked as they say: without labelling to the son, as in most chapters of the book was used, although he that desireth variety may now use both: For the Amicantifer labeled from the centre of the Astrolabe unto the sons place in thecliptic as in the book is used, either itself or one of his three cross fins shall show you the hour in the hour quadrant of the Cursor, so you take those hour numbers which fit unto the direction of the fin written thereon: that is to say, if the Matutine or Pomeridian fin come thereon then the numbers from 1 to 6 must serve: if the Antemeridian or Vespertine then those from 6 to 12.  
The second thing most material to be done is as in the 10 & 17 cap. I endeavoured to show to choose out on the Zenitfer the points & lines appertaining to your latitude, Horizon, or place of your abode, & to prepare him with his furniture to the Horizon of that place: Which having now four Cursors you shall do & understand I hope with ease. And for more facility as well in working as numbering, you shall reject the odd minutes of your latitude, if any happen, and work upon the nearest entire degree as in all ancient Astrolabes the use ever was until practise hath made you more perfect for the minutes. For example, to prepare the Zenitfer to the latitude & Horizon of Reading, where the latit. or poles elevation is by the 10 cap. to be found about 51 2/3 deg. you shall in steed of 51 2/3 take 52 deg. and account that for our latit. neglecting the odd 20 min. which for common use will hurt little. Wherefore you shall seek out this latit. 52 among the radiall degrees of the nooneline, where I have in this figure set E, & there to plant the fiducial line of your Vertical leaguer in the former figure marked with O. Then likewise seek the same 52 latit. among the radial deg. of the North line where I have set R, & there to plant the horizontal leaguer Q. And between those 2 lidgers thus placed you shall ever find 90. radial deg. of the Zenitfer as if you tell them with a stick as they say you may easily try, now the 20 min: be rejected, & those 90 ra. deg. are the 90 intersections of the 90 Almicantares with the North quadrant of the Meridian in every latit. & therefore I call them the North deg. Then seek out twice 52 deg. uz. 104 degrees in the Northline reckoned from the centre outwards which will fall out at 14 deg. without the ✚, where I have set X and there plant the Azimuthall lydger P. And these 3 thus planted shall never be stirred so long as you keep in the 52 latit. Then to proceed further if now you follow the fiducyall line of the Vertical lydger thus planted cross the Zenitfer from E, you shall perceive it of itself, to find out & touch the Zenith point of your latitude, that is to say, the innermost end of that Zenith line which appertaineth to the 52 latit. marked with F, whose outer end is marked with B, this line B F is the Zenith line of the 52 latit. & all the rest of his fellows are of no use in that country, yet is he jointly with them divided by the cross slope lines which you see into 90 parts, though unequal which are as in the 1 cap. is said, the 90 Almicantar roots that is to say out of these 90 roots severally doth spring the 90 several Almicantares or circles of altitude of the 52 latit. which roots are easily reckoned by the upright numbers set in the left margin unto every 10 of them. And because these roots begin from the outer-most ends, & thence are numbered inwards, therefore the point B being the outer end of the 52 Zenith line, is the root of the first or 0 Almicantare of this 52 latit. which in deed is always the Horizon itself. For the Almicantares begin from the Horizon & thence grow less & less till they come to nothing at the Zenith, as the parallels grow from thequinoctial to the pole, where they end at 90, so that ever the Horizon circle is the first or 0 Almicantare. This well understood them shall you set the fiducial line A D of the Cursor even with the point B on the Zenitfer & there plant him fast with a screw pin, if your work be of metal & so shall he cut the noneline at A, thence apply the fiducial line G F of the Almicantifer in the former figure even with the noon line, & thereon slide down the finger of the pointer till it touch the horizontal lydger at the point X there screw fast the pointer also. Lastly you shall from the point X where the Azimuthall leaguer resteth extend his thread even with the noon line, & there slide up the pearl till it touch the Vertical leaguer at E, & there knit the pearl fast with a knot never to be stirred in the 52 latit. And so at the last (your three lidgers thus placed at E R & X & the Cursor to B A & the pointer distant from A according to the quantity A R & the pearl from X according to X A) your Zenitfer is prepared to the Horizon of this 52 latitude, which being done (once for all as they say) performeth all the Chapters of the book without any altering or removing, some 2 or 3 Chapters excepted, for which the Cursor only is to be removed but none of the rest, and therefore in regard thereof the labour is short though it seem long.  
The Zenitfer thus prepared to the Horizon of the 52 latitude & the Howercircles Index set to the ☉ as before, for the day and time proposed, you may then presently even with one bare inspection see almost half the conclusions of the book performed without any labour at all more than to apply the nooneline unto that planet carat or star which you mean to work upon.  
Example: the 5 day of March 1598. proceeding as in the 5. cap. is taught, you shall find the ☉ his place in thecliptic 25 degr. 3 min. in ♓ thereto direct the Index of the howercircle by help of the Noonelyne. Where let him rest fixed for all that day, so have we no more trouble with that part. And now will we here work upon the great star of the first magnitude which you see in the face of Taurus commonly called Palilicium Aldebaram or Oculus tauri to know his state in the heavens. His longitude is easily descried as in the 2 cap. is showed by the circles described on the Celestial, to be about 4 deg. & an half, and his latitude in like sort to be almost 5 degrees Southwards from thecliptic, for all the Stars which have North latitudes, even the one half of the globe are in this Astrolabe comprehended within the Zodiac.  
Then do but apply the Noon line of the Zenitfer as before prepared, unto the middle prick or centre of this star Oculus tauri, it shall there show you in the Matters limb 62. deg. and better his right ascension and in thecliptic circle four degrees and better in ♊ his deg. of culminacon as in the 8 cap. and in the hour circled almost half an hour past 4 of the clock afternoon the time when as he shall that day culminate or come unto the meridian in the South part, as in the 16 cap. And thus much the bare line showeth you. Now do but mark what point or radiall degree of the nooneline cutteth upon the middle prick of the Star, & that point shall play as good a part, for if you reckon that point or degree according to the numbers set on the noon line, you shall find it 16 deg. and better, and so much is the declination of Oculus Tauri as in the 8 cap. and that Northwards from thequinoctial circle because he is within it. Then reckon by the radiall de. on the nooneline counting them from the vertical leaguer (set to the latitude as before) till you come to that 16 degree over the cnetre of the star, you shall find them amount to 36, & so much will his distance from our Zenith be, when he cometh to the meridian, which 36 deg. taken out of 90 leaveth 54 degrees his Meridian altitude as in the 16 cap. And if you turn about the Zenitfer till the North line of Media nox come on this star, so shall the nooneline also (whose office alone is now to show the hours) show you half hour past 4 in the morning and better, the just time when as Oculus Tauri shall come unto the Meridian in the North under the earth. And now if you list to remove the hour circles, Index from day to day the noon line (resting still on the star) may show you what hour that Oculus ♉ cometh to the Meridian every day of the year.  
And as all those Meridian conclusions, (as I may term them) are soon had by bare inspection without moving. So you may as readily attain all the horizontal conclusions with a very easy kind of motion: but even with leading about the Zenitfer by the Almicantifer, as one should lead a horse by the halter round about an horse mill, and all the skill is but to know which way to lead him, for if your question proposed be, to be performed on thest half of the Horizon, which I call the East hemisphere (for the Meridian or nooneline always divideth every Horizon in two equal parts) then must your Almicantifer play on the East or left side of the nooneline where Oriens is written, and lead him about leftwards till the pointer touch upon the planet or star proposed, but if on the West hemisphere than right-wards: as for example, to know what hour the ☉ shall rise the said 5 of March 1598. play your Almicantifer in the East hemisphere and thereby lead about the Zenitfer left-wards till the pointer may be borough to touch the said 25 deg, 3 mi. of ♓ there shall the nooneline show you in the hour circled almost a quarter after 6 of the clock, the time of son rising that day, and the Almicantifer labeled to the East line of the Zenitfer, vz, to L M showeth as in the 17 Chap. in the Celestialls' limb 355 1/2 deg. his obliqne ascension for that day. Then if you list to lead him on leftwards till the pointer come to touch the middle prick of Oculus Tauri, there you shall see the nooneline to show in the howercircle a little past 9 in the forenoon the time of his rising that day, and the Almicantifer labeled or applied from L on M, shall show in the Matters limb 41 deg. his obliqne ascension for that day as in the 18 cap. And if now you would know what time they will set, then play the Almicantifer on the West hemisphere, and by him lead about the prepared Zenitfer right-wards till the pointer do touch either of them, and you shall so find the nooneline to show for the the son almost 6 of clock, and for Oculus Tauri the times of their setting, almost 12 at midnight. And the Vespertine fin of the Almicantifer G I applied to L M so shall the fiducial line G P F of the Almicantifer which representeth now the West line show in the Matters limb the 354 1/● deg. and for the star 86 deg. their obliqne descensions for that day. Then if you reckon the hours between the Son rising and setting the same is the length of the day, and those taken out of 24 leaveth the length of the night also, the hours between the rising & setting of Oculus Tauri are called his diurnal arch, those taken out of 24 leaveth his Nocturnal arch. Likewise the right ascension of Oculus ♉ being as before 62 deg. and now his obliqne ascension found 41 degree take the bigger out of the less there resteth 21 deg. his difference of ascension in this 52 latitude from that of the right Horizon.  
To perform the 15 Chap. apply the Noonelyne to the ☽ and from thence reckon in the howercircle set, so many hours either rightwardes or left-wardes according as you find the hour given by his shade, distant from the Index and at the end of that reckoning is your desire.  
Now to the example of the 23 cap. if you plant the noneline on the great Star Oculus Tauri, the howercircles Index planted at 26 deg. 3 min. of ♓ seek thereon, 10 of the clock at night the hour given and thence reckon thereon the hours unto the noon line, you shall find then 5 2/3 hours those shall be the hours distance of Oculus Tauri from the South there sought, and that Westwards because the reckonning goeth Westwards from 10 of the clock.  
Next to the 24 cap. the howercircles Index planted (for still that must first be done) at 20 de. 10 min. ♎. In steed of labelling to thee ☉ you shall apply the nooneline to 10 of clock in the morning, in the howercircle, and there holding still the Zenitfer, prepare it as before is taught to some altitude at adventure, admit to 20 degrees: then playing about the Almicantifer if the pointer so set will come to touch the Sun his place or star proposed, then be sure that altitude prepared is your desire, but if the pointer over reach as at that proffer it will. Then holding still the Zenitfer at the hour given, prepare it to a greater altitude, admit to 25 deg. at adventure, and then playing about the Almicantifer you shall find the pointer to cut thecliptic in the 20 deg. 10 min. of ♎ at K being the sons true place for that instant. Therefore you may conclude that the 10 of October 1596 at 10 of clock in the morning the Son was 25 deg. high in our 52 latit. if 25 had not hit you must have assayed again if need had been.  
LAST of all for Addition in the use, take one devise more with you for the Azmuth then before I wrote of: which with no small study I attained, meaning to have reserved it with divers other propositions that I have in store for a second edition. But because carpers shall not say that my so commend Astrolabe wanteth any needful part that other Astrolabes had. I will here though I could perform it 2 or 3 ways for brevity only deliver the best. As to the example before mentioned, where according to the altit. of the ☉ taken 25 degree high by the Zenitfer prepared to that 25 altit. and the pointer applied on the Sun his place at K, his nooneline showed in the howercircle 10 of clock. There hold fast the Zenitfer till you have done, if you desire also to know what Azimuth the ☉ was than in. And play about the Almicantifer (it is no matter on which side of the nonneline) till it will meet at G. justly with the pearl (prepared as before) of the thread fastened in the loop of the Azimuthall lydger at X their hold also fast the thread X G. Then apply the fiducyall line of the Almicantifer even with the fiducial line of the Cursor square crossing the Zenitfer: And so slide them square down together till the Almicantifer cut the pearl at G. which will be at H. in the nooneline, & there at H. fasten the Cursor & slice the pointer to G. & then unhitch the thread from X & hitch it to the vertical leaguer at E, & from E extend the thread on the Sun's place at K, lastly play about the Almicantifer till the pointer settled at G as before do touch the Vertical thread E K, which will be at I. H I. being equal to H G. So doth H I. the fiducyall line of the Almicantifer cut among the Antemeridian degrees of the Cursors Azimuthall quadrant, 57 deg. the Azimuth sought for. That is to say, the degrees cut are to be taken by the outer numbeing being it was in the morning because the Azimuthes are numbered from the East and West points of the Horizon either-way unto the Meridian there ending at 90, which is to be regarded by the letter P on the Almicantifer.  
And out of this proposition (because we will leave no hard chap. of the book unexplaned) you may easily learn how to perform the 20 chap. another way. For by another Synonomy of speech to know the amplitude of rising and setting of the Sun, or stars, is but to know upon what Azimuth or point of the compass they rise. Wherefore being that the Horizon circle of any place is the beginning of the first circle of altititude that is to say, of the 0 Almicantare. Therefore to get this amplitude, you must first prepare your Zenitfer to that 0 altitude, that is to save, to the Horizon as before is taught by setting the Cursor to A D. and the pointer to R. from A. And being so prepared, if it be for son rising let the Almicantifer play in the East Hemisphere, and his pointer there touching the Sun's place, hold fast the Zenitfer till you have all done, whose noon line showeth in the howercircle his hour of rising. Then for the Azimuth work in all respects as is done last before, and you shall find the meeting of the pearl and pointer at G. will fall out in the centre line L. M. extended. Wherefore if a thread were hitched in the centre L. and his pearl extended beyond M. to that crossing at G. the Cursor need not here be removed at all from A. D. when the one thread is extended out of the Vertical point E on the ☉ & this thread out of L till pearl out that vercal thread as before he did at I this centre thread shall show in the limb of the Celestial the amplitude desired, desired, If you reckon thence to 6 of clock that is to say; unto that degree which the 6 of clock, howerline of the howercircle would show in the Celestial limb, if it were extended.  
Note that if any man shall affect to have the howercircle on the Zeniifer according to the first direction: and not on a plate or flat by itself as now I appoint him. Yet let him quite out away the Pomeridian hours which are without the Zenitfer numbered from noon unto media nox, to to the end that nothing may hinder the sight of the whole Hemisphere at all times and that the Cursor may always have free passage to the centre. And then to use in steed of the centre thread a rule or label, like unto the Almicantifer before described, with the Vespertine sin only. For so shall the rule show the Antemeridian hours from midnight to noon and the fin the Pomeridian from noon to midnight, and all by that one half hour circled described on the Zenitfer even as before it was done on the quadrant with three fins, and as readily as in the book by the whole circle.  
FINIS.   

Paultes escaped in the Book.  
In the 9 Chap. 2 line, for passeth by the Zenith. read passeth from the Pole by the Zenith.  
In the 18 Chap. the 18 & 22 line, for 280 & 19 Read 180 and 29.  
In the 27 Chap. line 61. for Inner end. Read outer end.  
Ibidem line 65. for outer end. read. Inner end.