The only curves which appear in the constructional lines of Louis XVI furniture are the geometric ovals and circles used frequently in chair backs, oval or circular gueridon tops, an occasional console support composed of two reversed semi-circles, or a regular section of an oval or ellipse in a chair or settee back. Irregular or free curves are never found.
The most typical feature in the constructional details of Louis XVI furniture is the leg. It is slender and tapering in chairs, generally fluted; the flutings of more costly chairs often filled for part of their length by husk-pattern carvings. A rounded moulding forms a collar at the upper end and a similar one, or a cup of acanthus leaves at the lower, the leg terminating in a plain cylindrical foot a couple of inches in height. In more elaborate pieces this foot is replaced by a moulded button as in the wide oval backed chair, in the Metropolitan Museum. Exceptions to the rule are alway true. The fluting frequently gives place in richer pieces to a rope effect. Two characteristic styles of chairs are where fluted architectural columns are used as supports, while in the other a square leg with a single canal takes the place of the usual round leg. The legs of Louis XVI furniture are always straight and taper downwards. Some of the commodes have a squat pedestal generally round but sometimes square.
At the corners of square seated chairs and the ends of mantels, or angle of a bed when a leg shaped half detached column is used, there is always to be seen either a square frame or an unframed platform of the same shape immediately above the leg. In chairs and other pieces of movable furniture, this square space is filled with a rosette, round or squared the most characteristic form when the square space is framed. The rosette is invariably round.
When the Pompeian style began to appear, the legs, while still tapering, were unfluted.
The arms of a wooden seat in the form of an armchair with open sides and upholstered arms, spring from the contour of the back and descend in a graceful curve to the required height with a padded cushion in the centre, and parallel to each other.
The typical Louis XVI arm is shorter than the depth of the chair and descends to its front corner in a smooth curve, carved with some classical moulding ornament such as the string of piastres or beads or one of the many variants of the meander or guilloche, or as on the exquisite settee, the stick and ribbon motive. The cresting ornament of this settee is a good example of the trophy of musical instruments which form so typical a feature of panel devices in the style of Louis XVI. The most common treatment of the cresting is a carved bow of wavy ribbon mingled with full blown roses and foliage. One rarely sees a piece of absolutely pure Louis XVI furniture.
The causeuse type of settee popular in the previous reign, still maintained its vogue under the new sovereign.
Chairs and settees were upholstered either with Aubusson or Beauvais tapestry, designed and shaped specially to fit the back, or in the smaller circular backed chairs and completely covered wing chairs in silk and satin striped material, always in delicate pastel tones as befitted so dainty a style as that of Louis.
The outstanding features of the style in ornamental detail are not necessarily impure. There are numerous exceptions to all rules in furniture making, and the individual taste of the customer was responsible in many cases for the very handsome freak pieces which apparently transgress every law of the masters who governed the designing in each of the major styles.