Witness allowance: entitlement, Registrar estimation, and deposit requirement govern payment and apply to interpreters. Rule prescribes that Government servants summoned may draw travelling and daily allowances under their service rules; where employer provision is absent the Registrar estimates an allowance sufficient to cover travel and other expenses reflecting the witness's status, which the summoning party must deposit before issuing the summons, and the same framework applies to interpreters with payment directed by the Appellate Tribunal if summoned as court witnesses.