Продолжить предложение 1) I. I. Mechnikov was bom in 2) Since his early childhood Mechnikov had became in- terested in 3) Mechnikov graduated from the University when he was only 4) In … Mechnikov became one of the leading professors of Odessa University 5) Twelve years later he left the University demonstrat- ing his protest against 6) In 1887 Mechnikov went and spent almost 30 years in

In 1795, a man named comte invented a pencil made of a mixture of graphite and some sorts of clays which were burnt in the furnace. "simple" pencils are made of graphite, which leaves a dark trail on paper. in the process of pencil manufacturing, dry graphite powder is mixed with clay and water. the more clay there is, the harder the pencil and the more graphite, the softer is the pencil. wood billets of cedar or pine are cut in half alongside and a groove is cut out for the lead. both halves of the pencil are then glued together. the billets are cut into pencils whose surface is polished. today more than 300 different kinds of pencils are produced for various purposes. there are pencils for writing and leaving trace on such surfaces as glass, fabric, cellophane, celluloid and plastic, which are used in construction .