Menno, sorry, but I have to 'edit' your response

Always terminate at the two ends of the line. In the schematic that would mean either at the master or on slave #1 and on the last slave.

You MUST create a line rather than a "star" network. it is essential to Keep branches as short as possible.

and add
It does not matter where on the network the 'master' is located at either end or somewhere in the middle, it is irrelevant.

At one or both ends use a weighing termination
Vcc 750R A 130R B 750R Gnd
if you weigh at one end only terminate the other with 120R.

You may want to read the thread about automatic termination.

Erik