1.   But the details have been obscured by time -- and because nobody thought to document the creation of what in those days was just another product.

2.   She and a former assistant once found an unused gas station that had been rented by an automaker and had several cars under thick coverings that obscured all details.

3.   They will be edited to obscure some details of the bombs, and will eventually be available to the public through the National Archives.

4.   He says Frei should have applied chemicals to remove surface coatings that obscure details of the pollen.