Firenze University Press www.fupress.com/substantia Preface It is a great honour for me to write these few lines of preface to the spe- cial issues of Substantia dedicated to the 150th anniversary of the Periodic Table by Dmitrij Mendeleev. In 2019 there are other important anniversa- ries besides that of the periodic table. One of these is the centenary of Primo Levi’s birth. I believe these two anniversaries are strictly related, in fact The Periodic Table by Levi has been considered by the Royal Institution of Great Britain as the “best book of science ever written”. It would be sufficient to recall an impressive excerpt from “Iron”, a tale of the The Periodic Table, to acknowledge the uniqueness of this literary work: “We began studying physics together, and Sandro was surprised when I tried to explain to him some of the ideas that at that time I was confusedly cultivating. That the nobility of Man, acquired in a hundred centuries of tri- al and error, lay in making himself the conqueror of matter, and that I had enrolled in chemistry because I wanted to remain faithful to this nobility. That conquering matter is to understand it, and understanding matter is necessary to understand the universe and ourselves: and that therefore Mendeleev’s Peri- odic Table […] was poetry …”. When we designed the project related to these special issues, we had in mind Levi’s work and in particular his wonderful tales that belong to The Peri- odic Table. I like to recall this homage to a chemist-writer-witness to introduce the six topics that are associated to the special volumes of Substantia. As President of the University of Florence which is the owner of the publisher Firenze University Press, I am truly grateful to the Editors – Marc Henry, Vincenzo Balzani, Seth Rasmussen, Luigi Campanella, Mary Vir- ginia Orna with Marco Fontani, and Brigitte Van Tiggelen with Annette Lykknes and Luis Moreno-Martinez – for accepting the invitation made by the Editor-in-Chief Pierandrea Lo Nostro and for the extraordinary work for the preparation of these special issues. Of course the choice of the six subjects was not accidental: we tried to identify some features of the chemis- try realm, related for several reasons to the periodic table. They are striking- ly associated to the great challenges for our future: these are water, sustain- ability, energy, open chemistry, the history and the educational perspectives of the periodic table. During its long path of progress and civilisation mankind has strongly modified nature to make our planet more comfortable, but at present we must be very careful with some dramatic changes that are occurring in our Earth. Science and technology, and chemistry primarily, can help mankind to solve most of the environmental and energy problems that emerge, to 8 SCIENTIFIC BOARD build a radically different approach from that that has prevailed in the last two centuries. It is a fantastic challenge, since for the first time we can con- sider nature not as a system to simply exploit, but a perfect ally for improv- ing life conditions in the whole planet. Chemistry has already engaged and won a similar challenge when, understanding the pollution problems gen- erated by a chaotic and rapid development, succeeded in setting up a new branch, green chemistry, that turned upside down several research top- ics. Now is the time to develop sustainable chemistry: the occurring events demand that chemists propose new routes and innovative approaches. In the last two centuries we have transformed immense amounts of matter from nature into waste without thinking that we were using non renewable energy sources. We have been acting as our natural resources were unlim- ited, but knowing that they are instead limited. Now we are realizing that it is not possible to continue along this road. Our planet and our atmosphere are made of finite materials and their consumption during the last two cen- turies has been impressive. Some elements that are crucial for current and future industrial countries are known to be present on Earth crust in very small amounts and their recycling from waste cannot be a choice anymore, but it is rather an obligation. Climate is another big problem associated to the terrific changes occur- ring in some equilibria, both as a consequence of the violent industrial devel- opment and energy consumption. We need, and we will always need more and more, an immense amount of energy. The only solution to secure well- ness to future generations is the conversion to renewable energy sources. In this view, food and water, due to the strong increment in the demographic indices, could become the true emergencies for billions of individuals. Look- ing at the picture I tried to draw in this short preface it becomes more clear why we selected those topics for our special issues. I am optimistic, and I have the strong confidence that chemistry, that studies matter and its transformations, will give mankind the picklock to overcome those challenges. We will definitely need insightful minds, creativity, knowledge and wis- dom. Luigi Dei President of the University of Florence Firenze University Press www.fupress.com/substantia Substantia An International Journal of the History of Chemistry Vol. 3, n. 2 Suppl. 4 - 2019 Firenze University Press The Periodic System, a history of shaping and sharing Brigitte Van Tiggelen1, Annette Lykknes2, Luis Moreno-Martinez3 Julius Lothar (von) Meyer (1830-1895) and the Periodic System Gisela Boeck Shaping the Periodic Classification in Portugal through (text)books and charts Isabel Malaquias1,*, João A. B. P. Oliveira2 The St Andrews Periodic Table Wallchart and its Use in Teaching R. Alan Aitken1, M. Pilar Gil2,* The periodic system and the Nature of Science: The history of the periodic system in Spanish and Norwegian secondary school textbooks Luis Moreno-Martínez1, Annette Lykknes2 Are History Aspects Related to the Periodic Table Considered in Ethiopian Secondary School ChemistryTextbooks? Gebrekidan Mebrahtu Order From Confusion: International Chemical Standardization and the Elements, 1947-1990 Ann E. Robinson Periodicity trees as a secondary criterion of periodic classification: its implications for science teaching and communication Alfio Zambon Compounds bring back chemistry to the system of chemical elements Guillermo Restrepo