It is more likely that said experiment took place in December 1897.

These difficult experiments took 3 years to complete and cost more than $1.4 million dollars.

The first Dutch experiments with television took place around the 1930s.

"Now, can you give us the time and date at which this experiment took place?"

The fact that the experiments took place isn't much of a secret at all.

This experiment will take several months to do properly, he said.

He used five female volunteers who knew the experiment was taking place.

This is further complicated if the experiment takes hours, days, or longer to perform.

The experiments took place in a period between 1944 and 1974.

I come from the country where this experiment took place.