The invention also relates to an arrangement in a spatial work of art.

A spatial work of art is known from US Patent Specification No. 5,407,392 wherein the work of art which is at least partially provided with transparent walls and includes cooling and heating elements for varying the temperature of the inside of the spatial work of art between a temperature below and a temperature above freezing temperature. By means of the arrangement, impressive phenomena are provided when water freezes and melts on a cyclic basis.

The present invention aims at further developing the above- described solution and at achieving an entirely novel type of method and arrangement in a spatial work of art.

The invention is based on generating an intense direct- current voltage field in the spatial work of art, said field controlling the formation of frost.

In more detail, the arrangement according to the invention is characterized by what is stated in the characterizing part of claim 1.

The arrangement according to the invention, then, is

characterized by what is stated in the characterizing part of claim 4.

The invention offers considerable benefits.

By means of the electric field, the formation of frost can be controlled and visually impressive "fluffy frost work" may be achieved.

In the following, the invention is described in more detail by means of embodiments in accordance with the annexed drawings.

Fig. 1 is a schematic front view of a spatial work of art according to the invention.

Fig. 2 is a perspective view of another spatial work of art according to the invention.

In accordance with Fig. 1, the spatial work of art 1 comprises a structure resembling an aquarium wherein typically all side walls are transparent. The spatial work of art 1 is typically thermally as carefully sealed as possible such that thermal losses into the environment are minimized. Thus, the spatial work of art 1 is typically closed at the top by means of a top board. In order to render temperature changes possible, a thermal device 4 is coupled to the apparatus, capable of both heating and cooling the internal part of the spatial work of art 1.

Said thermal device 4 typically comprises a compressor-type

cooling apparatus of the kind used in refrigerators and freezers. By means of a medium, the cooling and heating effect is applied to desired targets inside the spatial work of art 1.

As target elements to be cooled/heated, spherical elements 5, flat elements 6 or devices 10 showing moving pictures, to cite a few examples, are provided inside the spatial work of art 1. The spatial work of art also incorporates a water pump 2 having a spout 3 for bringing water into the spatial work of art in the form of mist, drops, or a stream. The amount of water can naturally be regulated.

According to the invention, a direct voltage is provided between the spherical elements 5 by means of a voltage source 11. The same measure has also been performed for the flat elements 6. The voltage source 11 is advantageously controllable and the voltage may vary from zero to even discharge voltage depending on the distance between the electrodes 5 and 6 and the current drip situation. The electrodes 5 and 6 having oppqsed polarities are naturally electrically isolated from each other.

The targets to be observed, such as the spherical electrodes 5, may be provided with zones which can be heated 9 or cooled 8. The zones may form figures or texts.

The device 10 which shows moving pictures may comprise a conventional projector embedded in the structure of the apparatus, a cathode-ray tube or a flat display such as an

electroluminescence display or a liquid crystal or plasma display. A cooling element may also be provided on the display 10 surface in order to enhance the impression created by the moving image.

As will emerge from Fig. 2, even smaller aquarium-type spatial works of art are feasible, whereby Peltier elements 20 serve as the cooling/heating elements. Such elements are commercially available and they weigh a few dozen grams.

When electric current is supplied to the element, part of it is cooled while part of it is heated. By reversing the direction of the current the cooling parts of the element can be heated, and vice versa. By suitably adapting such Peltier elements 20, a desired target can be both cooled and heated by means of electric current. In the Figure, some of the Peltier elements 20 are covered with plastic whose colour changes according to the temperature. In this manner, colour effects of a desired kind can be achieved.

Peltier elements are also provided at the barrel 25 bottom, whereby the temperature of the liquid inside the barrel 25 can be varied by means thereof. The liquid 21 inside the barrel 25 may comprise water or advantageously a vegetable base oil having a congealing point which is higher than the freezing temperature of water. Preferably, rapeseed oil is used as the vegetable base oil. Due to the heat of transformation of oil which exceeds that of water, the transformation phenomena such as the formation of crystals 23 may be performed with less consumed energy. The splendour of the phenomena may be underlined by colouring the oil.

All walls of spatial works of art are typically transparent. However, all variations from one to four transparent walls are possible within the scope of the invention.

As a source of light in the spatial work of art, illuminators made of optical fibres may be used whereby no thermal power is transmitted to the spatial work of art.

The liquid in the barrel 25 may also be made to circulate in a cooled/heated circulation system which at least partly consists of a transparent material.

Some or all of the wall elements of the spatial work of art may be made semipermeable whereby the permeability of the mirrors as well as the visibility of the various details of the spatial work of art from the outside may be influenced by adjusting the level of illumination inside the spatial work of art.