A chemist is a scientist trained in the study of chemistry. Chemists study the composition of its properties. Chemists describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms. Chemists measure substance proportions, reaction rates, other chemical properties; the word'chemist' is used to address Pharmacists in Commonwealth English. Chemists use this knowledge to learn the composition and properties of unfamiliar substances, as well as to reproduce and synthesize large quantities of useful occurring substances and create new artificial substances and useful processes. Chemists may specialize in any number of subdisciplines of chemistry. Materials scientists and metallurgists share skills with chemists; the work of chemists is related to the work of chemical engineers, who are concerned with the proper design and evaluation of the most cost-effective large-scale chemical plants and work with industrial chemists on the development of new processes and methods for the commercial-scale manufacture of chemicals and related products.

The roots of chemistry can be traced to the phenomenon of burning. Fire was a mystical force that transformed one substance into another and thus was of primary interest to mankind, it was fire. After gold was discovered and became a precious metal, many people were interested to find a method that could convert other substances into gold; this led to the protoscience called alchemy. The word chemist is derived from an abbreviation of alchimista. Alchemists discovered many chemical processes. Chemistry as we know it today, was invented by Antoine Lavoisier with his law of conservation of mass in 1783; the discoveries of the chemical elements has a long history culminating in the creation of the periodic table by Dmitri Mendeleev. The Nobel Prize in Chemistry created in 1901 gives an excellent overview of chemical discovery since the start of the 20th century. Jobs for chemists require at least a bachelor's degree, but many positions those in research, require a Master of Science or a Doctor of Philosophy.

Most undergraduate programs emphasize mathematics and physics as well as chemistry because chemistry is known as "the central science", thus chemists ought to have a well-rounded knowledge about science. At the Master's level and higher, students tend to specialize in a particular field. Fields of specialization include biochemistry, nuclear chemistry, organic chemistry, inorganic chemistry, polymer chemistry, analytical chemistry, physical chemistry, theoretical chemistry, quantum chemistry, environmental chemistry, thermochemistry. Postdoctoral experience may be required for certain positions. Workers whose work involves chemistry, but not at a complexity requiring an education with a chemistry degree, are referred to as chemical technicians; such technicians do such work as simpler, routine analyses for quality control or in clinical laboratories, having an associate degree. A chemical technologist has more education or experience than a chemical technician but less than a chemist having a bachelor's degree in a different field of science with an associate degree in chemistry or having the same education as a chemical technician but more experience.

There are degrees specific to become a chemical technologist, which are somewhat distinct from those required when a student is interested in becoming a professional chemist. A Chemical technologist is more involved in the management and operation of the equipment and instrumentation necessary to perform chemical analyzes than a chemical technician, they are part of the team of a chemical laboratory in which the quality of the raw material, intermediate products and finished products is analyzed. They perform functions in the areas of environmental quality control and the operational phase of a chemical plant. In addition to all the training given to chemical technologists in their respective degree, a chemist is trained to understand more details related to chemical phenomena so that the chemist can be capable of more planning on the steps to achieve a distinct goal via a chemistry-related endeavor; the higher the competency level achieved in the field of chemistry, the higher the responsibility given to that chemist and the more complicated the task might be.

Chemistry, as a field, have so many applications that different tasks and objectives can be given to workers or scientists with these different levels of education or experience. The specific title of each job varies from position to position, depending on factors such as the kind of industry, the routine level of the task, the current needs of a particular enterprise, the size of the enterprise or hiring firm, the philosophy and management principles of the hiring firm, the visibility of the competency and individual achievements of the one seeking employment, economic factors such as recession or economic depression, among other factors, so this makes it difficult to categorize the exact roles of these chemistry-related workers as standard for that given level of education; because of these factors affecting exact job titles with distinct responsibilities, some chemists might begin doing technician tasks while other chemists might begin doing more complicated tasks than those of a technician, such as tasks

The Gatwick Stream is a tributary of the River Mole in southern England. The Gatwick Stream rises in Worth Forest below Clays lake in West Sussex, flows northwards through Tilgate Forest, alongside Tilgate golf course, through Maidenbower, Three Bridges, Tinsley Green to meet the River Mole on the border between West Sussex and Surrey. Native species of fish found in this stream include Brown Trout, Dace, Pike, Millers Thumb, Brook Lamprey, Stone Loach and Minnow. 1) Raise the dam at Clays Lake to provide enlarged flood storage protecting passengers of the London-Brighton main line railway people living in Maidenbower, Crawley. 2) Provision of a new flood detention dam at Worth Farm to add additional resilience to flood alleviation of the M23 motorway. 3) A river restoration scheme at Grattons Park nature reserve, involving the replacement of the existing straight concrete channel with a natural meandering earth channel. 4) The raising of the dam at Tilgate Lake to provide additional flood storage, protecting hundreds of homes vulnerable to flooding in Furnace Green, Pound Hill, Three Bridges, Tinsley Green and Horley.

Crawley Sewage Treatment Works is located adjacent to the stream, downstream of Crawley and discharges up to 15 Ml of water per day into the river. River Mole

Ouvrage Restefond is a work of the Maginot Line's Alpine extension, the Alpine Line. The ouvrage consists of one artillery block and three observation blocks at the summit of the Col de la Bonnette; the entry block and an artillery block were not completed, a further block was never built. At 2,733 metres, Restefond is the highest Maginot ouvrage. Block 1: one machine gun cloche and one heavy twin machine gun embrasure. A 47mm anti-tank gun was planned. Block 2: one machine gun cloche and two 81mm mortar embrasures. Block 3: one machine gun cloche and one heavy twin machine gun embrasure. Block 4: one observation cloche, one machine gun cloche and one heavy twin machine gun embrasure. Block 5: three 75mm gun embrasures. Block 6: three 75mm gun embrasures, intended for indirect fire. Block 7: three 75mm gun embrasures proposed to be armed with a twin 75mm gun turret. Restefond includes 668 meters of underground galleries at a depth of 64 meters; the position remains the property of the French military, with much of its equipment intact.

Some of the uninstalled equipment remains at the Restefond barracks nearby. See Fortified Sector of the Dauphiné for a broader discussion of the Dauphiné sector of the Alpine Line. Block 6 fired on Italian forces in June 1940. List of Alpine Line ouvrages William; the Maginot Line 1928-45. Oxford: Osprey Publishing, 2003. ISBN 1-84176-646-1 Kaufmann, J. E. and Kaufmann, H. W. Fortress France: The Maginot Line and French Defenses in World War II, Stackpole Books, 2006. ISBN 0-275-98345-5 Kaufmann, J. E. Kaufmann, H. W. Jancovič-Potočnik, A. and Lang, P. The Maginot Line: History and Guide and Sword, 2011. ISBN 978-1-84884-068-3 Mary, Jean-Yves. Hommes et Ouvrages de la Ligne Maginot, Tome 1. Paris, Histoire & Collections, 2001. ISBN 2-908182-88-2 Mary, Jean-Yves. Hommes et Ouvrages de la Ligne Maginot, Tome 4 - La fortification alpine. Paris, Histoire & Collections, 2009. ISBN 978-2-915239-46-1 Mary, Jean-Yves. Hommes et Ouvrages de la Ligne Maginot, Tome 5. Paris, Histoire & Collections, 2009. ISBN 978-2-35250-127-5 Rimplas at fortiff.be Patrimoine XXeme, Ouvrage Restefond