english: The rods are of different metals - three of brass for the bass and seven of [iron, steel or copper] for the middle and treble range.
non_english: Â 1903:Â 20 Jan (ru);Â Â Â Â 17 Freb (ru);Â Â 18 Mar (ru);Â Â Â Â 21 Apr (ru);Â Â Â Â