It means:

> From which it is easy to conclude that these equations could not contain the time _t_

i.e. are independent of time. 

- _sauroient_ is old for _sauraient_ from _savoir_ (I think). (Maybe not real "[Old French][1]" which is officially before 1,300. But yes, nobody uses that today anymore). 

- _ne savoir renfermer_ would be an expression meaning, roughly, _ne pouvoir renfermer_, i.e. _cannot contain_.


  [1]: https://en.wikipedia.org/wiki/Old_French