Military Architecture

‘I shall propound some general Rules or Principles of Fortification, approved and owned by many skilful Captains and Engineers.’

Hendrik Ruse, The strengthening of strong-holds p. 3.

Hendrik Ruse, The strengthening of strong-holds: invented on several occasions, and practised during the late wars, as well in the United Provinces, as in France, Germany, Italy, Dalmatia, Albania, and the neighbouring countries (London, 1668), plate 4 (fortifications).

Hendrick Ruse (1624-1679) conceived of his book on fortifications as a short treatise on practical matters: it wasn’t designed to set out the mathematical underpinnings of military fortifications since, as he said himself, ‘The Principles of War are not always limited to Mathematical Rules’, but rather was intended as a practical guide to demonstrate how built fortifications might be additionally strengthened. This is particularly apparent in his comments on the above plate – the aim was to add additional safeguards rather than construct a fortification from scratch:

‘For the first Figure are shewed three several manners of Counter-guards, being all three very good and commodious, and may be very fitly applied to places, that are already Fortified; as also the Royal Work, and the great Wall may be redressed in such places, with little charge, after this way. The second and third manner of Counter-guards I count better, when the place and occasion permitteth it, to make them so large, for they are extraordinarily Advantageous…’

Ruse was addressing the city councillors of Amsterdam, to whom The Strengthening of strong-holds was dedicated. These included Cornelis de Graaff who had played a major role in bringing the building of the Stadhuis of Amsterdam to completion. The Stadhuis symbolised Amsterdam’s trade with the world but it was, as Ruse suggested to his patrons, a trade and a city which needed to be protected.

Ruse presents us with 20 ‘Maxims or general Rules which are observed in the Modern Fortifications.’

There ought to be no point of the whole Fortification undiscovered or unflanqued, and that some several places of Defence.
The Lines defending ought to be longer then the Lines defended, or at least as long.
A Regular Fortification is very much stronger then an Irregular.
The more Bastions a Regular place hath, the greater is its Strength and Defence.
A Fortress ought to command all places whatsoever round about.
Those parts of a Fortress which are nearest to the Center, ought to command those that are more remote.
Those parts of a Fortification which are at greatest distance from the Center, ought always to be Commanded by those that are nearest the Center.
The Line of Defence Fichante, ought not to be much longer then 60 Rods, that being the distance ordinarily allowed for the Port of a Musket.
The larger the Flanques and Gorges are, the better and stronger they are, provided the other parts are not prejudiced thereby.
Of second Flanques, and Courtine-Flanques, the larger is the better, in case it cause no disproportion in the other parts of the Fortification.
As for the Linea Stringens (or Line of Defence Secant, which is continued from the Face to the Courtine) the shorter it is, the better, if the Flanques be not too much lessened by it.
That opening of the Angle of a Bastion is the best, which gives a right length to the Flanque, second Flanque, and Gorge.
The Angle of a Bastion ought not to be less then 60 degrees, nor greater then a Right Angle, or 90 degrees.
The Angle of the Poligone ought not to be less then 90 degrees.
The Angle of the Face and Flanque ought to be at least 150 degrees.
The Angle of the Courtine and Flanque ought to be evermore 90 degrees, or a Right Angle.
The outward Angle of Defence (or Angle Flanquant) cannot well be too Acute.
The inward Angle of Defence ought not to be less then 25 degrees.
The proportion between the Courtine and the Face ought to be as 3 to 2, or as 36 to 24.
The Faces should never be longer then the Courtine, nor shorter then one half of the Courtine.

Underlying these are a series of mathematical equations which he examines in detail.

Unusually, Ruse gives us quite a lot of information about himself in his preface to the reader. We hear that he had joined the army of the States of Holland at the age of 15, and, having fought for them for around four years, joined the French army in order to increase his military experience. His experiences fighting in France and Germany during the Thirty Years War showed him many methods of fortification, but did not sate his appetite for new military experiences, and he therefore travelled via Switzerland and Venice to Dalmatia, to fight Ottoman Turks. From there he returned to Venice and then home to Germany – at which point he attached himself to the service of the City of Amsterdam. It is clear that this autobiographical passage had a serious intent – to display the range of his expertise to his new masters.

Worth’s copy is unusual in that it does not have the engraved title frame which is present in other copies of the same edition. It does, however, have an important provenance note:

‘To his worthy Friend Mr David Loggan
A great Master
Of the Arts of Perspective, Drawing, Grauing,
Etching, Painting.
A great Lover of
The Arts of Fortification Architecture Surveying &tc
Sir Jonas Moore freely presents this Booke.

May ye 16th 1682.’

The artist and engraver, David Loggan (1634-1692) had a connection with Amsterdam, having studied engraving there with the younger Crispijn de Passe (c.1597–1670) before journeying to London, where he settled sometime between 1656 and 1658 – the latter being the year in which Ruse’s work was printed. Perhaps best known as a portrait engraver, Loggan is also famous for his engravings of the University of Oxford. Sir Jonas Moore (1617-1679), who presented him with Ruse’s book, was a mathematician and patron of astronomy. For a brief period, he had taught James, Duke of York, arithmetic, and following that, had become surveyor to the fifth earl of Bedford’s fen drainage company. During the Second Dutch War (1665–7) he was appointed temporary assistant surveyor of the royal ordnance and would later become Surveyor General of the Ordnance. He himself published works on military architecture, such as his Modern Fortifications (1673).

Johann Bernhard Fischer von Erlach, Entwurff Einer Historischen Architectur: in Abbildung unterschiedener berühmten Gebäude des Alterthums und fremder Völcker; umb aus den Geschicht-büchern, Gedächtnüß-münzen, Ruinen, und eingeholten wahrhafften Abrißen, (fortified country house).

Ruse concentrated on strengthening buildings which were already fortified but the principles he proposed were equally applicable to other buildings not normally fortified. As this image from Fischer von Erlach’s history of architecture demonstrates, military fortifications were not solely for cities, towns or castles, but could also, potentially (and if the owner had enough money to implement them), be added to private dwellings. How effective they were is less clear.

Composite image of Bernard de Montfaucon, L’antiquité expliquée, et représentée en figures (Paris, 1719), 5 vols. in 10, Suppl. vol. 4, plate 17 (battering ram) and vol. 4, pt. 1, plate 91 (siege tower).

In this composite image from Worth’s copy of Bernard de Montfaucon’s L’antiquité expliquée, et représentée en figures (Paris, 1719) we see two methods often used in laying siege to a town : a ‘battering ram’ was used to ‘ram’ into the walls and was here given the head of a ram ; the siege tower, to the right of the image, was not only mobile to enable moving it up adjacent to city walls, but has, in this instance, been embellished with corinthian columns.

Sources

Tyack, Geoffrey, ‘Loggan, David (bap. 1634, d. 1692)’, Oxford Dictionary of National Biography, Oxford University Press, 2004; online edn, Jan 2008.

Willmoth, Frances, ‘Moore, Sir Jonas (1617–1679)’, Oxford Dictionary of National Biography, Oxford University Press, 2004; online edn, April 2016.

Text: Elizabethanne Boran, Librarian of the Edward Worth Library.