On Some Geometrical Aspects of Land Surveying in the Middle Ages

On Some Geometrical Aspects Of Land Surveying In The Middle Ages
VERENA CASENSKY
INTRODUCTION
As to the fact that quite a number of publications deal with the innova­ tions in geometry and mathematics on the verge of early modern times,1 but only few discuss land surveying during the Middle Ages, this paper is dedicated to the explanation of some of the main sources of errors made in land survey during this epoch, as witnessed by contemporary authors, and to show how farfetched the knowledge on some aspects of land surveying was.
Literature on the subject is scattered and quite a few studies are found in publications out of reach of the historian. Klaus Grewe has recently compiled a bibliography on the subject.2 In general, two elds have drawn the attention of research: First, the historical point of view, coping with the determination of the actual size of old measures in cer­ tain regions,3 or with metrological problems mainly.4 Secondly, geodetic surveyors dealing with historical subjects concentrate highly on mere technical details of certain instruments. Besides that, if they deal with theoretical aspects in the historians‘ eld, the outcoming studies are in some cases not meeting the historians‘ quality standards.5
1 See, as an ex p le, the studies on Regio ontanus‘ life and work, recently, e. g., Günther Hamann (ed.), RegiomontaiUs-Stu en (= Veröfef ntlidlungen der Kom­ mission f Geschichte der Mathematik, Naturwissenschaften und Medizin 28,29,30) Vienna, 1980.
2 Klaus Grewe, Bibliographie zur Geschichte des Vermessungs sens (= Schriften­ reihe des Förderkreises des Vermessungste sdlen Museums) Cologne, 1984.
3 Walter Kuhn, Vergleichende Untersuchungen zur mittelalterlidlen Ostsiedlung ( Ostmitteleuropa in Vergangenheit und Gegenwart) Cologne, Vienna, 1973, p. 150 f. 4 Fritz Böni•ch, Zur Auflösung von Vermessungsanga n in geschichtlichen Quellen. : Heimatkunde und Landesgeschichte, ed. iedrich Bec (= Veröffentlichungen des Brandenburgischen Landeshauptar ves 2) Weimar, 1958, p. 135-150.
5 An exBltlple for this is Paul Stichling, Die P ege der Geschichte des Vermessungswe­ sens I. : Zeits rift f Vermessungswesen 74 (1949) 91. More recently: Volker
Biala•, Die Geodäsie und ihre Geschichte – wissenschaftstheoretisdle Aspekte ( Geschichte und Entwicklung der Geodäsie, E 22) Munich, 1984, p. 23, ann. 1.
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=
=
Astronomy, although using the same instruments,6 deals with dif­ ferent problems, as does navigation.7
SOURCES
For this study two sources have been selected: First, the „Geometria Culmensis“,8 written between 1393 and 1407 by order of Conrad von Jungingen, being Grand M ter of the Teutonic Order at that time. It was chosen due to the fact that it is one of the very few sources ap­ pearing not only in Latin, but well in Middle High German, whereas, e. g., the geometrical tractate of Robertus Anglicus, written in 1271, was translated only in 1477.9 A treatise written in the vernacular may Iead to the assumption that it was dedicated to practical use. The second source discussed i� this study is the „Practica Geometriae“, dating om the end of the 12th century.10
A study of land surveying in the Middle Ages cannot leave out Ger­ bert’s works on the subject. Werner Bergmann11 points out in his study that Gerbert w using land surveying a perfect example for both geometry and tronomy, not dealing in particular with the problems arising during practical work. It seems important though, that Gerbert w obviously using the „Corpus Agrimensorum Romanorum“ as source for his own studies.12
6 See, e. g., Fritz Schmidt, Geschichte der geodätis en Instrumente und Verfahren im Altertum und Mittelalter (= Verö entli ungen der Pfälzis en Gesells a zur Förderung der Wissens aften 24) Neustadt/Haardt, 1935, p. 22.
7 The main proble of navigation is the localisation of a moving point on a map grid. For this, exact measurement of time is absolutely necessary, as the degree of longitude cannot be measured otherwise.
8 Edited : Urkunden und ende Quellen zur deutschen Ostsiedlung im Mittel­ alter(= Ausgewählte Quellen zur deuts en Geschichte des Mittelalters I, . v. Stein Gedächtnisausga XXVI a), ed. Herbert Helbig, Lorenz Weinrich(Darmstadt, 1968) p. 524-531,n. 143.
9 Schmidt, Geschichte der geodätis en Instrumente, p. 24, ann. 69.
10 Ma an Curtu, Practica Geometriae. Ein anonymer Traktat aus dem Ende des zwölften Jahrhunderts. In: Monatshefte f Mathematik und Physik VIII (1897) p. 193-224.
11 We er Bergmann, Gerbert von Aurillac und die Landvermessung. In: Inge­ nieurvermessung von der Antike bis zur Neuzeit 3, Sym sium zur Vermessungs­ geschi te in Dortmund 16. 2. 1987, ed. Hartwig Junius (Dortnrund, 1987).
12 Bergmann, Gerbert, p. 109 and 138, ann. 12.
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For the various other sources on land surveying the reader is asked to consult Fritz Schmidt.13 Generally, sources tend to deal more with the theoretical aspects of the problem, as, e. g., determination of the earth’s circumference, than with the practical problems. This is also shown by Volker Bialas,14 who, although dealing with early modern times mainly, has been pointing out that during the Middle Ages theoretical problems absorbed the scientists‘ thought. Even after the beginning of the sea­ faring age, when the interest in problems of navigation and cartography increased, sources are dealing with purely geometrical problems more than with problems of what we would nowadays call applied science. As one of the very few examples for the opposite, the „Tractatus Geometriae Practicae“ by Martinus Polonus15 should be mentioned here.
SOLUTIONS OF SURVEY PROBLEMS IN THE MIDDLE AGES
Theory
Distance me urement is in fact a comparison of two distances: The one you know (your measure) and the one you want to know. This is also true for area measurement, where you compare with an area unit which gives the area of a plane piece of land by multiplication.
Although this sounds easy, and is in fact theoretically easy, various sources of errors can be found. In the Geometria Culmensis we nd on the subject: Nec oportet ex hoc super ciem mensurandam quadratam esse, quod mensuratur per super cies quadratas, ymmo triangulus et poligonia et super cies irregulares et circulus mensurantur super cie qua­ drata. Ideo dixi, quod oportet, super ciem famosam et notam esse qua­ dratam, que debet esse mensura aliarum super cierum, cuiusque dispo­ sitionü exi&tant.16 It had to be explained that the square could be used as a standard for area determination of circular or else shaped pieces.
Determination of heights and depths not accessible to direct mea­ surement present one of the problems, sources frequently deal with. The length of a distance not completely in sight of the surveyor (e. g. on a hill) gives the second one. I will only deal with planimetric proble1ns here.
13 Schmidt, Ges ichte der geodätischen Instrumente, passim.
14 Volker Biala•, Praxis Geometrica. Zur Geschichte der Geodäsie am Beginn der Neuzeit (= Ges ichte und Entwic ung der Geodäsie E 11) Muni , 1970.
15 Mag. Martini de Zorawica alias „Martinus Rex de Premislia“ vocitati Geometriae practica seu artis mens ationem tractatus, ed. L. Birktnmaj�r (Warsaw, 1895).
16 Geometri Culmensis, p. 528.
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It has to be stressed that the shape of the piece of land to be sur­ veyed is most important. In reality, we will come upon irregular forms a Iot more often than upon perfect squares and rectangles. For irregular polygons determination of angles is necessary for area measurement. All these problems are independent of the actual size of the measure used.
Practical Aspects
For practical survey the unit of measure is of central importance. Stan­ dardization of me ures for length and area is a di cult task, as can be judged om the 19th century work on the „meter-standard“ which w prepared with the utmost accuracy possible, b 1t had no theoreti­ cal foundation. Only nowadays a theoretical basis which is not subject to any possible change has been created for the meter by using the wavelength radiated by a defined atomic process. No wonder that the medieval society had its problems with standardization as well. Units of length were primarily taken from the only standard accessible to every­ one everywhere: the human body. The Geometria Culmensis is a vivid example for standardization on human measures, saying … in der Hand­ breit $teckt viermal der Finger, viermal im Fuß die Hand …17 Medieval sources show that people were aware of the bi due to di erences of this me ure,18 but accepted the bias, as the availability of the measure was the greater opportunity compared to its stability.
Human me ures, apart from their variation present another pro­ ble to the surveyor: Their size very small compared to the sizes of the pieces of land to be measured. Direct comparison would have been extremely tiresome and erratic. Strings with knots in regular intervals could be used for the measurement of larger distances. As they were made out of natural fibres, large di erences in their actual measure oc­ curred depending on the relative air humidity or on the wetness of the ground they were laid upon. Metal chains, which are described in the Geometria Culmensis as well as the strings, were not susceptible to this bias, but were heavy and thus unpracticable for transport over large distances, additionally representing quite some value at that time.19
All these instruments, as well as the pole, which was quite frequently used even later, as the experimental determination of its length by av­ era ng the foot measure of 16 chosen people shows,20 have one major
17 Geometria C ensis, p. 531.
18 Urkunden und erzählende Quellen, p. 524, n. 142.
19 Biala1, Praxis Geometrica, p. 4.
20 Biala1, Praxis Geometrica, p. 2, reporting a procedure described by Köbel in 1522.
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disadvantage: They imply direct access to the distance to be measured. This system has its limitations in the measurement of large extensions, as were usual in land survey. Estimation of usual sizes is possible from the de nition of the „Joch“, which was the area which could be ploughed with a yoke of oxen in one day. For a study on the development of this measure, see the publication of Egghart.21
In the following, some examples for the solution of geometrical pro­ blems in the sources are given to illustrate the medieval standard of knowledge.
The Geometria Culmensis gives the right formula for the area of a triangle, mentioning that taking the length of a side of a triangle in­ stead of the height (as shown in Fig. 1) causes errors in measurement.
Fig. 1: Area of a triangle
Formula: A = a * h{a)/2
Er tic medieval version: A * = a * b/2 Inthü case: a=60,b=50,h(a)=40
A = 60 * 40/2 = 1200mm2
A * = 60 * 50/2 =1500mm2
Error: A * amounü to 125% compared to A
a
21 K t Egghart, D Österrei is e Joch und seine keltis -gallis e Wurzel. : Österrei is e Zeits rift Vermessungswesen 53 (1965) p. 153-162.
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Errors due to implementation of (b) – one side of a triangle – in­ stead of h(a) – height of triangle over the baseline – can amount to several percent of the area to be measured, depending on the shape of the triangle.
One might wonder why triangles are of such importance to the un­ known author ofthe Geometria Culmensis, as we usually find reetangular pieces of land. Most pieces are not reetangular in fact, and those irreg­ ular polygons can only be measured by dividing them into triangles. It w quite usual, even in the 16th century, as discussed by Bönisch,22 to calculate the area of irregular pieces with four sides by averaging two and two of them and treating those averages with the formula applicable to rectangles (see Fig. 2).
Fig. 2: Polynom area determination
Rectangle: A = a * b
a
Polynoms we treated with the same formula using the arithmetic means of two sides:
A*= (a+c)/2•(b+d)/2
Gorreet sults a obtained by splitting the polynom into triangles using the area determination according to Fig. 1.
Inthiscase:a= 30,b=40,c=48,d=50 2 A*= ((30 + 48)/2) * ((40 + 50)/2) = 1755mm •
Gor et calculation yields (e = 30, h1 30, hz = 47): A=30* 30/2+30* 47/2= 1155mm2
Er r: A * amounts to 152% compared to A.
22 Böni.ch, Z A ös g, p. 141 f.
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b

For the 14th century Kuhn23 notes that the surveyors tried to mark out pieces of land almost reetangular and regularly shaped, which might have to do with the easiness of surveying in such cases.
The measuring instruments were known to Gerbert and are de­ scribed in detail by Schmidt.24 The commonly known instruments were the gnomon and a cross-like shaped piece called crucze in the German version of the Geometria Culmensis. For both instruments two ways of application were possible: they could be put on the earth’s surface and the distances to be measured would then be measured with strings spanned in the directions indicated by the cross, or they were used for a1mmg.
Aiming is the most e cient means of minimizing the expenses of surveying procedures. Two mathematical laws are implied in this proce­ dure: First the similar rectilinear gures theorem, describing such gures as having their several angles equal each to each, and the sides about the equal angles proportional. This not only provides a tool for the measurement of distances out of reach (as, e. g., the width of a river25), but presents a possibility of surveying a very !arge area by building a figure with the same proportions out of twigs or similar material, which then could be measured much easier.26 Fritz Schmidt explains the use of an instrument for this purpose, made of three sticks with regular marks of which two were connected on one end, opening up a variable angle. The third stick was used to adjust the shape of the construction according to the proportions of the piece of land to be measured. The advantage then was not only the lessened practical expense, but also the
23 Kuhn, Untersuchungen, p. 64 and 150.
24 Schmidt, Ges ichte der geodätischen Instrumente, p. 115. 25 Bergmann, Gerbert, p. 123.
26 Kuhn, Untersuchungen, p. 150.
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avoidance of any calculation,27 only the unit of measurement had to be changed and the marks could easily be counted.
With the second example it can be shown that, in spite of the description in Gerberts oeuvre written almost 400 years ahead of the Geometria Culmensis and the detailed remarks on the subject in the Practica Geometriae two centuries earlier, the author of the Geometria Culmensis still had to complain about the errors made in the calculations implied in aiming. Fig. 3 shows the principal problem.
Fig. 3: Aiming
The height of the u.rveyor ha to be taken into calcu.lation, following: a2+ b2= c2,thu. a= Jc2-b2
Inthi ca e:a= 70,b=24,c= 74
a=
The er r of approz. 5% in length i mu.ltiplicated du.ring area calcu.la­
42 –
tion, leading to mu.ch greater er r .
242
= 70
-·-. -·- c
. ·-·-. -. -.
a
27 Schmidt, Geschi te der geodätischen Instr ente, p. 372. 14
. .
In mmg you start making errors in the moment you stand up, insteadofworkingasneartothesurfaceaspossible. Asintheriverwidth example the height of the surveyor has to be included in the calculation, this time by application of the Pythagorean theorem, which was known to the authors.
The Geometria Culmensis gives a good approximation for the square root calculation, which was needed in the Pythagorean theorem by split­ ting the number into two parts, following:
fo= Ja2+ b� a+ bf2a
where a is the nearest square number. For x = 250, 225 ful lls this pre­ requisite, being the square of 15, thus = 15 + 25/2 * 15 resulting in = 15.833. A comparison to the calculated number = 15.811 shows that the deviation is only 0.14 %, a negligible amount.
Even better agreement with calculated values is achieved in the ap­ proximation given for the nurober , in this case cited from the Practica Geometriae, as it follows the older sources (e. g. Gerbert) as well as the Geometria Culmensis:28 is approximated by 22/7, which gives a value of 3.1428, compared with the real value of 3.1416 making up a di erence of 0.04 %. This deviation is of no interest in practical measures, even if values as big as the earth’s circumference are to be calculated with this approximation.
It was mentioned above that the surveyor could adjust the shape of the pieces to be surveyed according to his possibilities if new land was to be cultivated. A slightly di erent sort of proble was given in cases, where existing areas were to be sized. One of the questions soluble only by application of the Pythagorean theorem is the question, if a piece of land was reetangular or not. This was of particular interest not for cultivation lands, but for places where buildings were to be erected. As the matter is discussed in Fritz Schmidt’s work,29 I will only brie y comment on it:
Reetangular triangles show certain proportions in the length of their sides, as described by Pythagoras. If one takes a piece of string with marks and constructs a triangle with such proportions one then has con­ structed a 90° angle as well. This is useful for determining rectangularity of existing structures as well as for constructing them.
28 Practica Geometriae, p. 216.
29 Schmidt, Ges ichte der geodätischen Instrumente, p. 98-101.
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REMARKS ON THE IMPORTANCE OF LAND SURVEY IN THE MEDIEVAL SOCIETY
Surveying unlike other scien c developments arising from practi­ cal needs of the people. Fritz Schmidt puts forward the building of houses and the transport of water through tubes as the origin of surveying.30 Although this is true, the real need for developing land survey methods definitely h been the determination of measures of cultivated Iands, as distance measurement itself does not imply area calculation which has been the driving element of theoretical development. No wonder that Egypt earliest sources have been found, as the yearly oods of the Nile made survey absolutely necessary.
Ancient Egypt fulfilled the second requirement for the development of land surveying much better than the Middle Ages did: A certain degree of organisation is necessary, as you need to have registration of me ures and education of personnel. The ‚Vogt‘ of the county of Ober­ schwaben, e. g., left the charter, which he had given concerning the width of a street, in the nearby Cistercian abbey of Salem, he had no measure registration of his own. This may serve as an example for the low degree of administrative development at that time.31 Routine me urements could not be performed under such circumstances.
The Geometria Culmensis shows which kind of social background enhances land survey studies: The Teutonic Order, having a high degree of inner organisation, cultivated large areas for the first time, thus the surveyors could determine the shape according to their needs. The need to survey large areas encouraged the development of indirect measure­ ment methods described above. Walter Kuhn32 gives details on the organisation of the Teutonic Order, but bis statement that the three­ eld-system of land cultivation enhanced surveying Iacks sound expla­ nation. He h the equally far-fetched argumentation that a correlation between the increased corn production and the land surveying methods e sts. In opposition to his findings it has to be stated that the actual measure of a field was of less importance to the possessor than its fer­ tility. Thus measures were relatively unimportant, if the di erence in fertility w high.
30 Schmidt, Ges i te der geod tis en lnstrwnente, p. 24, . 69.
31 Heim; Thomru, Deuts e Ges i te des Spätmittelalters 1250-1500 (Stuttgart, Berlin, Cologne, Mainz, 1984), p. 44.
32 Walter Kuhn, Neue Beiträge zur S lesis en SiedlungsgesdU te (=Quellen und Darstellungen zur S lesis en Ges i te 32) Si ar ingen, 1984.
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Nevertheless, the re-development of land survey was enhanced by the colonisation of large areas as weil as the increasing administrative Ievel and furthermore by the beginning of seafaring and the reappearance of antique sources, many of them coming through the arabic scientists‘ work.
Acknowledgments:
The idea to thia atudy, as weil as my t German version of it, originate from a course in medie l history held by Herwig Weigl of the „Institut f Österrei ische Ges i tsfors ung“, Vienna. His guidance is gratefully acknowledged. I also owe a Iot to Chriatina Roaenberg, who has been giYing me many helpful hints conce ng English tranalations of acientific papers.
Address of the author:
Verena Casensky Sechshauserstraße 91/2 A -1150 Wien
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MEDIUM AEVUM QUOTIDIAN UM
NEWSLETTER 16
KREMS 1989
Herausgeber: Medium Aevwn Quotidiam . Gesells a zur Erfors ung der ma­ teriellen Kultur des Mittelalters. Kö ermarkt 13, A-3500 Krems, Österrei . – F den halt verantwortli zei nen die Autoren, ohne deren ausdriiekli e Zu­ stim ng jeglicher Nachdru , auch in Auszügen, nicht gestattet ist. – Druck: HTU-Wirtschaftsbetrieb Ges. m. b. H., Wiedner Haupstraße 8-10, A-1050 Wien.
Inhaltsverzeichnis/Contents
Vorwort 4
Vera Casensky:
On Some Geometrical Aspects Of Land Surveying
In the Middle Ages ……………. ……………….. ……… 7 Verzeichnis der Mitglieder von
„Medium Aevum Quotidianum“ 18 Besprechungen – Berichte – Mitteilungen 26
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Vorwort
Im letzten, Dänemark gewidmeten Heft hat Medium Aevum Quotidia­ n m begonnen, sich mit den in einzelnen Ländern durchgeführten For­ schungen zu Alltag und materieller Kultur des Mittelalters auseinander­ zusetzen. Diese begonnene Reihe wird, wie angekündigt, fortgesetzt: die Vorbereitungen für Heft, dessen Gegenstand die Situation in Finn­
land sein wird, sind soweit gediehen, daß Herbst mit dem Erscheinen zu rechnen ist. Gleiches gilt für ein Heft, welches die diesbezügliche Lage in Ungarn zum Inhalt haben wird. Kontakte mit schwedischen Kollegen zur Realisierung eines ähnlichen Vorhabens wurden aufgenommen.
Der zweite Schwerpunkt der Verö entlichungstätigkeit wird auf der Fortführung von Auswahlbibliographien zu Teilbereichen der Geschichte von Alltag und materieller Kultur des Mittelalters liegen. In den näch­ sten Heften werden wir eine auf Ungarn bezogene Bibliographie vorlegen können, sowie eine solche, deren Schwerpunkt auf Südosteuropa liegt. Ferner wird die bereits angekündigte Auswahlbibliographie zu „Kleidung und Mode in Mittelalter und früher Neuzeit“ zur Pub ation kommen. Schließlich ist für 1990 mit dem Erscheinen einer Auswahlbibliographie zum Thema „Migration in Mittelalter und früher Neuzeit“ zu rechnen sowie einer kommentierten Auswahlbibliographie zum mittelalterlichen Schi swesen.
Das vorliegende Heft soll einerseits vor allem der Information unse­ rer Mitglieder dienen. Einige aktuelle Ankündigungen sowie die aktua­ lisierte Mitgliederliste unserer Gesellschaft sind in diesem Sinne zu ver­ stehen. Andererseits widmet sich der verö entlichte Beitrag zur Land­ vermessung im Mittelalter einem Themenbereich, der unseres Erachtens nach von großer Wichtigkeit für unser Forschungsfeld ist, jedoch in der wissenschaftlichen Aufarbeitung einigermaßen vernachlässigt wird. Der Autorin sei für die zur Verfügung Stellung der Arbeit gedankt.
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Die Vorbereitungen für die von Medium Aevum Quotidianum in Zu­ sammenarbeit mit dem Institut für mittelalterliche Realienkunde Öster­ reichs der Österreichischen Akademie der Wissenschaften für 1990 in Krems geplanten internationalen Veranstaltungen sind weit gediehen. Vom 9. bis zum 12. Oktober 1990 wird der Kongreß „Alltag und Kommu­ nikation im Mittelalter“ statt nden. Ein Teilbereich dieses Themenkrei­ ses wird ausgekoppelt und im Rahmen eines Round-Table-Gespräches am Montag, dem 8. Oktober 1990, zur Sprache kommen. Es handelt sich
dabei um die Problematik von „Alltag und Wallfahrt im Mittelalter“. Die Liste der jeweils vorgesehenen Referenten bzw. Teilnehmer sowie die zu behandelnden Themen stehen zum Großteil fest. Ein konkreteres, vorläufiges Programm werden wir im nächsten Heft unseres Newsletters mitteilen können. Die endgültigen Programme werden Ende des Jahres zum Versand kommen.
Die Vorbereitungen zur Publikation der Ergebnisse der Veranstal­ tungen des Jahres 1988 schreiten ebenfalls voran. Der Band zum Round­ Table-Gespräch „Religiöse Stiftung und materielle Kultur im Mittel­ alter“ wird in Kürze in Druck gehen und noch 1989 erscheinen. Der Band des Kongresses „Mensch und Objekt im Mittelalter. Alltag – Le­ ben – Kultur“ wird in der zweiten Jahreshälfte in Druck gehen können und 1990 vorliegen. Beide Bände werden �ls Verö entlichungen des Instituts für mittelalterliche Realienkunde Osterreichs 12 bzw. 13 im Rahmen der Sitzungsberichte der philosophisch-historischen Klasse der Österreichischen Akademie der Wissenschaften zur Publikation gelangen.
Das Institut für mittelalterliche Realienkunde Oster ichs feierte vor einigen Wochen die ersten zwanzig Jahre seines Bestehens. Aus diesem Anlaß fand nicht nur ein kleiner Festakt statt, sondern es wird darüber hinaus auch eine Bibliographie aller Publikationen zur Verö entlichung gelangen, die seit dem Bestehen aus und im Rahmen der Institutsarbeit entstanden. Ergänzt wird diese Bibliographie durch den Abdruck des Festvortrages von Wolfgang Brückner, Würzburg, zum Thema „Der Blu­ menstrauß Realie. Gebrauchs- und Bedeutungswandel eines Kunst­ produkts im christlichen Kult seit dem Mittelalter“.
Eine �esonders enge Zusammenarbeit entwickelt sich augenblicklich unter der Agide von Medium Aevum Quotidianum zwischen ungarischen und Österreichischen Forschern. Daraus ergibt sich nicht nur die Reali­ sierung der oben angeführten Publikationsvorhaben, sondern eine weit darüber hinaus gehende Kooperation. Diese beinhaltet regelmäßige ‚fref­ fen kleiner Gruppen von Wissenschaftlern, sowie vor allem die Förderung
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junger, noch in der Ausbildung stehender Kollegen durch gezielte Inte­ gration in den Diskussionsprozeß. Unsere Gesellschaft hat das Ziel, sol­ che und ähnliche Bestrebungen internationaler Kooperation weiterhin verstärkt zu initüeren oder zu vermitteln sowie aktiv zu unterstützen. Diesbezügliche Anregungen und Vorschläge werden gerne entgegenge­ nommen.
Gerhard Jaritz
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