Boros István (szerk.): A Magyar Természettudományi Múzeum évkönyve 3. (Budapest 1953)
Boros, I.: The exhibitions of the Hungarian National Museum Museum of Natural History
how and why they originate. They illustrate old and new notions about the structure of crystals, the investigations of Laue, the point system, network, space lattice ; the structure of native copper, rock salt, pyrite and zircon ; then an atomic modell illustrates our conception of atomic structure; and, separately, the structure of hydrogen, helium, sodium, and argon atoms. The material of cases 14—16 exhibit processes by which information may be gained with regard to the formation of minerals. Their respective chapters are : igneous, sedimentary and metamorphic occurrence and association of minerals ; minerals of igneous origin mineral deposits of magmatic origin ; of liquid, magmatic, pneumatolitic and extrusive magmatic origin ; of extrusive magmatic origin ; sedimentary pangenesis (local, mechanical and chemical sediments) ; salt deposits ; the role of water, oxygen and carbon dioxyde ; the weathering of minerals ; places ; metamorphosis of mineral associations. Among exhibits we have used not only minerals, of course, but also every installation which, by artistical means, is apt to clarify and to make understandable the contents of the explanatory texts. So, for instance, models, prints, drawings, paintings, maps, etc., but always in a way that they disturb not the general impression, in the middle of the first room we have displayed two unique pieces of our Museum, which will demand the attention of even the most indifferent public : a grandiose smoke quartz, weighing 133,5 kilogramme, known as »Granddad« in literature, of which no bigger specimen is known ; and an amethyst mineral group of several hundred kilogramms, consisting of 5—10 centimetres long dark violet crystals. The second and third room, as I have already mentioned above, displays minerals, according to the results of crystal chemistry. In the second room there are 17 cases exhibiting, in systematical order, minerals ranging from the native elements to the carbonates ; in the third, 15 cases, showing their sequence from the sulphates to minerals of organic origin. In the middle of the second room are, in a free standing metal frame .glass case, the most celebrated representatives of our rich meteorite collection. For the sake of information, there are exhibited, beside of the above displays, 554 minerals, 25 prints, 45 drawings and one Table, in the second room. As far as it was possible, we tried to lay stress, besides the instructive points of view, on the artistical setting of the material ; and to proceed in the methods of installations and the application of didactic instruments (maps, prints of mines, cross sections, etc.) not stereotypically but to augment harmony and to emphasize- importance. We know it well that the above display of mineralogical systematics does not illustrate consequently the processes of crystallogenesis in natural conditions and so it does -not concentrate on the connection of surrounding and mineral genesis or the dynamics of their origin and the associations of minerals. As, however, according to this conception, mineral systematics should be introduced by the silicates, the most complicated and for the learning of basic principles the most difficult group, our above plan seemed the more suitable from the didactic point of view also, because in the fifth room, in connection with the external forms and origin of ores, the visitor will have ample information on all these problems ; and, besides, we had already alluded to it in the introductory part of room I. The fourth room exhibits the material of petrography, arranged in the following themes : The world of rocks ; The origin of rocks ; Igneous, sedimentary and metamorphic rocks ; The family tree of igneous rocks ; The external form of igneous rocks ; The most important igneous rocks ; The origin of sedimentary
