"B...Balthazar. B...Balthazar. B... Balthazar. BALTHAZAR!!!" A show must be doing something right if a theme song as moronic as that can stick in your head for 25 years like a Beatles song.
From the former Yugoslavia, or Serbia, or.... God, I get confused about that countr(ies), this series of short episodes emerged in the late 60's, and for some reason was a big international hit (relatively speaking. How many other Yugoslavian cartoons from the 60's or 70's can you name?) which was played, if not all over the world, then over a goodly portion of it, And then played again and again, at least into the early 80's.
Who was Balthazar? Well he was your typical, kindly, eccentric professor, who would get into some problem, or be presented with some dillemma, and solve it by means of a big contraption which extruded some potion fit for the occaision. To the best of my memory there was no dialog, which lent it a bit of a Bruno-Bozzetto-ish feel, if you're looking for a current analog.
What made it so memorable? I'm damned if I know. It's just one out of the blur of shows through my childhood and teen years that lodged in my head because I liked it. I wish I could remember more, so as to say something more informative or to be confident enough to give it a stronger rating, but I feel sure 2.5 is in the right region.
I'd love to see it again. I'd recommend it, but I have no idea where you're going to find it, this side of a cable channel in Zagreb.