Felix Hoffman  was born on 21st January Genery 1868 in Ludwisgburg, Germany. He was a German chemist known for having synthesized acetylsalicylic acid following the method of Arthur Eichengrün and allow the production of aspirin.

Useful forms of heroin and aspirin,while he was employed as a chemist  at BayerAG.He was a pharmaceutical and he was invented aspirina.He did important discoveries  and studied in  University of Munich.

Also  on Agust 1897 synthezised for the first time in stable form usable form medical applications. Hoffman moved to the pharmaceutical marketing departament, where he stayed until his retirament in 1928.In 1894  he joined the Bayer as a research chemist.

I got the information and photo google images on the wikipedia .

John Boyd Dunlop was born on 5th February 1840 in Dreghorn,  North Airishirer. He was from Scotland. He lived in Edinburgh and Belfast, Ireland. He studied in Edinburgh Veterinary College. He was a veterinary.  He worked for 8 years in veterinary medicine in Edinburgh. He moved to Belfast. He did an important discovery. He was 47 years old when he invented  the first fire with air chamber. He died on 23th October 1921 in Dublin.

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He was born in the U.S. the 19th of July julay, 1894. His father died when he was 3. He was an engineer and inventor. He left school when he was 12. He was known as the inventor of the Microwave. He was the vicepresident of the Atministrtion Council in Raytheon. Spencer got married and had 3 sons. He died on the 8th of September, 1970.