Вставьте артикль где необходимо.when edison was … boy of fifteen he worked as … telegraph operator. he had to be on … duty from 7 p.m. to 7 a.m. and give … signal every hour to prove that he did not sleep. … signals were made with … stonishing exactness. one night … inspector arrived and saw edison sleeping on … chair. he was about a to shake
him when he caught … sight of … mechanism on … table near … telegraph instrument. he waited to see what would happen. when … hand of … clock pointed to … hour, … instrument got busy and one level threw open … key while … other sent … signal over … wire. … inspector seized … sleeping boy, roused him and fired him. that is why … first of edison’s numerous
inventions was never patented.

When Edison was a boy of fifteen he worked as a telegraph operator. He had to be on  duty from 7 p.m. to 7 a.m. and give a signal every hour to prove that he did not sleep. The signals were made with  a stonishing exactness. One night  an inspector arrived and saw Edison sleeping on  the chair. He was about  a to shake him when he caught  a sight of the mechanism on the table near  the telegraph instrument. He waited to see what would happen. When  a hand of the clock pointed to an  hour, the instrument got busy and one level threw open the key while  other sent  a signal over the wire. The inspector seized the sleeping boy, roused him and fired him. That is why the first of Edison’s numerous inventions was never patented.