Based on the provided legal document, the key points are as follows:

1. The provisions of the Indian Stamp Act, Madhya Pradesh Stamp Rules, 1942, and the Evidence Act apply exclusively to instruments that qualify as "instruments" within the meaning of section 2(14) of the Stamp Act. These provisions do not extend to copies of instruments (!) .

2. An instrument, as defined, refers to the original document that creates, transfers, or records rights or liabilities. A copy of such an instrument is not considered an instrument under the Stamp Act and cannot be validated or impounded as an instrument (!) .

3. The law clearly states that a copy of an instrument cannot be validated by impounding or admitted as secondary evidence under the Stamp Act. This is because secondary evidence of an unstamped or insufficiently stamped original instrument is not permissible unless the original is produced and properly stamped (!) (!) (!) .

4. When an instrument bears a stamp of sufficient amount but of improper description, provisions under the Stamp Act and Rules allow the Collector to certify the document as duly stamped upon payment of the proper duty. However, these provisions only apply to original instruments, not copies (!) (!) (!) (!) .

5. The Madhya Pradesh Stamp (M.P. Amendment) Act, 1990, introduced Section 48-B, which permits the Collector to require the production of the original instrument when a deficiency of stamp duty is noticed from a copy. This section does not authorize the impounding of copies but only the production of original documents for verification (!) (!) .

6. The authority to impound or act upon a document is limited to original instruments. The impounding of copies or secondary evidence is not supported under the Stamp Act or the Rules, and the law emphasizes that only original instruments, properly stamped, are admissible in evidence (!) (!) .

7. In cases where a document is improperly stamped, the proper course involves paying the requisite duty and obtaining certification from the Collector that the instrument is duly stamped. This process does not include impounding or validating copies that are not original instruments (!) (!) .

8. The provisions for recovery of stamp duty or penalties are restricted to original instruments. When deficiencies are identified from copies, the Collector's role is limited to demanding the original for inspection rather than impounding or validating the copy (!) (!) .

9. Overall, the legal framework underscores that only original, properly stamped instruments are relevant for impounding, validation, or secondary evidence purposes. Copies of instruments, especially when original documents are lost or unstamped, cannot be validated or admitted as evidence under the Stamp Act (!) (!) (!) .

10. The case-specific facts involve an agreement that was improperly stamped with a notarized stamp of Rs. 4/- instead of the required Rs. 1/-. The courts held that such a document, being an original instrument with improper description, could be rectified through certification by the Collector if the proper duty was paid, but copies or secondary evidence could not be substituted or validated as original instruments (!) (!) (!) .

In summary, the legal principles affirm that only original instruments, duly stamped, can be impounded, validated, or admitted as evidence. Copies or secondary evidence are not considered instruments under the Stamp Act and cannot be validated by impounding or certification unless they are the original document itself.