Across
- 2. An official right to an invention
- 4. Buying and selling services
- 6. It is an iron rod that is used to make lightning strike it
- 7. The result of a series of chemical changes in the blood.
Down
- 1. The study of blood and blood disorders
- 3. A person connected with the invention of the Arch Lamp
- 5. A train travels along a path of two metal rails, or tracks