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  SEAL, conveyancing, contracts. A seal is an impression upon wax, wafer, or 
  some other tenacious substance capable of being impressed. 5 Johns. R. 239. 
  Lord Coke defines a seal to be wax, with an impression. 3 Inst. 169. 
  "Sigillum," says he, "est cera impressa, quia cera sine impressione non est 
  sigillum." This is the common law definition of a seal. Perk. 129, 134; Bro. 
  tit. Faits, 17, 30; 2 Leon 21; 5 John. 239; 2 Caines, R. 362; 21 Pick. R. 
  417. 
       2. But in Pennsylvania, New Jersey, and the southern and western states 
  generally, the impression upon wax has been disused, and a circular, oval, 
  or square mark, opposite the name of the signer, has the same effect as a 
  seal the shape of it however is indifferent; and it is usually written with 
  a pen. 2 Serg. & Rawle, 503; 1 Dall. 63; 1 Serg. & Rawle, 72; 1 Watts, R. 
  322; 2 Halst. R. 272. 
       3. A notary must use his official seal, to authenticate his official 
  acts, and a scroll will not answer. 4 Blackf. R. 185. As to the effects of a 
  seal, vide Phil. Ev. Index, h.t. Vide, generally, 13 Vin. Ab. 19; 4 Kent, 
  Com. 444; 7 Caines' Cas. 1; Com. Dig. Fait, A 2. 
       4. Merlin defines a real to be a plate of metal with a flat surface, on 
  which is engraved the arms of a prince or nation, or private individual or 
  other device, with which an impression may be made on wax or other substance 
  on paper or parchment, in order to authenticate them: the impression thus 
  made is also called a seal. Repert. mot Sceau; 3 McCord's R. 583; 5 Whart. 
  R. 563. 
       5. When a seal is affixed to an instrument, it makes it a specialty, 
  (q.v.) and whether the seal be affixed by a corporation or an individual the 
  effect is the same. 15 Wend. 256. 
       6. Where an instrument concludes with the words, "witness our hands and 
  seals," and is signed by two persons, with only one seal, the jury may 
  infer, from the face of the paper, that the person who signed last, adopted 
  the seal of the first. 6 Penn. St. Rep. 302. Vide 9 Am Jur. 290-297; 1 Ohio 
  Rep. 368; 3 John. 470. 12 ohu. 76; as to the origin and use of seals, Addis. 
  on Cont. 6; Scroll. 
       7. The public seal of a foreign state, proves itself; and public acts, 
  decrees and judgments, exemplified under this seal, are received as true and 
  genuine. 2 Cranch, 187, 238; 4 Dall. 416; 7 Wheat. 273, 335; 1 Denio, 376; 2 
  Conn. 85, 90; 6 Wend. 475; 9 Mod. 66. But to entitle its seal to such 
  authority, the foreign state must have been acknowledged by the government, 
  within whose jurisdiction the forum is located. 3 Wheat. 610; 9 Ves. 347.