Most early hooks are 4 wire There is...
the only difference is that one set should hopefully make contact after the first set when phone goes off hook.
Ideally this same set that Makes Last should also Break first meaning when hung up, it should be the first open set.
This set is Breaks first and makes last
Then there is the other set that breaks last and makes first
The purpose of this is connect the phone spkr element AFTER the phone goes off hook and to break the connection to speaker element BEFORE the phone goes back on hook.
Most Western Electric candlesticks (20-AL, 40-AL, 50-AL, 51-AL) have 3 contact springs, not 4, as originally designed for use with a sidetone subset. The 4-spring 120-ALs and 151-ALs are conversions where the hookswitch was replaced for use with anti-sidetone subsets.
When using a mini-network, 425-type network, or 685A subset with a 3-contact hookswitch, only 2 of the contacts are used, to open one side of the line and hang up the phone. There is no way to avoid the pop in the receiver (unless maybe you add a varistor in parallel with the receiver to reduce the pop somewhat).
With the 4-conductor hookswitch of a 151-AL, 120-AL, or 152-AB, you can use one set of contacts to open the line, and the other set to open the receiver. As stated above, you would want the receiver contacts to open first when hanging up, and to make last when going off-hook.