You don't actually need a measuring tool to measure gravity directly. We can determine the strength of gravity through observation and calculations. Here's how:

* Observation: We observe how objects fall. The acceleration due to gravity (g) is the rate at which an object's velocity changes as it falls. This can be measured using various methods, like dropping objects from a known height and timing their descent.

* Calculations: We can calculate the gravitational force using Newton's Law of Universal Gravitation. This equation uses the masses of the objects involved (like the Earth and a falling object) and the distance between their centers.

Here's what we actually use:

* Pendulums: A pendulum's swing period is directly related to the gravitational acceleration. By measuring the period, we can calculate 'g'.

* Gravimeters: These specialized instruments measure the local gravitational field strength. They are used in geological surveying and other scientific applications.

* Accelerometers: While not specifically designed for gravity, accelerometers can be used to measure the acceleration of a falling object, which directly corresponds to the gravitational acceleration.

So, while we don't have a single tool called a "gravity meter," we use various methods and tools to determine the strength of gravity based on its effects on objects.