DRACULA II: THE LAST SANCTUARY

In the sewers, take the direction for Highgate. Almost instantly, Jonathan finds his way blocked by rats and cannot go on.
In the inventory, combine the VLS with the crank to power it.
To manipulate the VLS in the inventory, click on the VLS (magnifying glass cursor).
To put the VLS in "reception" mode, click on the left on the button down below (a kind of rectangle). The VLS moves into reception position, ready to detect waves. You then return automatically to the scene, where an "aerial" cursor appears.
Position the "aerial" cursor on the rats. The VLS reacts. The dials are illuminated and emit a sound.
Go back into the inventory and click on the VLS to see what frequency the rats have emitted.
Display the same value on the other screen, using the round button.
Go into "transmission" mode. Click on the right of the rectangular button this time. The button moves to the right and you return automatically to the scene.
Position the "aerial" cursor on the rats again and click. They will run for cover into the next-door passage.
Take the passage leading to the main sewer.