Observed
Part of speech: verb
Definition: To notice or view, especially carefully or with attention to detail.
Example sentence: I am opposed to the laying down of rules or conditions to be observed in the construction of bridges lest the progress of improvement tomorrow might be embarrassed or shackled by recording or registering as law the prejudices or errors of today.
Ascertained
Part of speech: verb
Definition: To find out definitely; to discover or establish.