Patent for tilt frame apparatus for transporting bulky cargo on truck is not invalid for failure to satisfy best mode requirement of 35 U.S.C. § 112, even though inventors did not state in specification that crane was preferred mode of carrying out method of loading and tilting frame, since deliberate concealment is not charged, and best mode requirement is not violated by unintentional omission of information that would be readily known to persons in field of invention, since reference in specification to manual rotation of frame and load is not evidence of concealment of use of crane, in that such method was not determined through experimentation, selection, or trial and error, and is not essential to practice of invention, and since it is undisputed that persons with experience in the field would know to use crane to move load.