Michelson-Morley experiment?

[Sonuz]

Could you please elucidate the below statement which is given as an objection to one of the possible explanation(earth drags the ether surrounding to it) for the negative result of Michelson-morely inferometer experiment?

A second objection arises from the fact that a transparent object of laboratory size does not drag the light waves with the full velocity of the moving matter, as it necessarily would do if it completely dragged the ether along with it; and the observed partial drag is fully accounted for by current electromagnetic theory

Thank you.

 

[Nugatory]

You will get more helpful answers if you provide the source of that quotation and tell us what you’re finding unclear

 

[Ibix]

The usual objection to ether dragging is that if the air can drag ether 100% (necessary for a null Michelson-Morley) then glass or water ought to, but Fizeau's experiments showed that it doesn't.

As Nugatory says, more detail on what you are reading and what you don't understand would help.