HOW TO EARTH SOMETHING IN REAL CIRCUIT?
Ok, there is a fundamental difference between earthing and what is described as grounding. What's probably confusing is the fact the earth symbol is used in the schematics you've linked as opposed to the more appropriate __|__ / / / / chassis ground symbol which was common in tube circuits as the circuit negative terminal was invariably the metal chassis that everything was bolted to. The chassis ground was sometimes earthed via the power supply to the input from the power socket ground/earth green lead. In radio circuits earthing is quite different and refers to an earth spike physically in the soil. So to summarize the earth symbols on both schematics merely refer to the fact that those points so marked should all be connected to the negative terminal of the power supply either directly, via a chassis or a common conducting copper bus bar.
in a breadboard take wire that is connected to ground, (use the wall outlet to get an earth terminal) and fix it in one of the lines then anywhere you need an earthing, or need a branch to take away extra current, you can use that line! now what you see in the circuit, is basically grounding, it uses the property that earth is considered to be at zero V and sets a reference . this is what it means physically you can take a wire from that terminal and connect it to the ground line as mentioned above earthing as a safety deive is slightly different in such a case, if a faulty wire were to touch the surface of a device, say an iron and charge it to 230 V then the earthing wire which is connected to the surface would conduct a huge amount of current, (the earthing wire has very little resistance) this would trip either the circuit breaker, or the ELCB, or if the device has a fuse, it would trip the fuse its the same principal that Earth is at 0V but its use os different, Earthing is safety, grounding is providing a reference . of course both can also be done by the same physical connection as per the circuit requirements
