Judgment : K. Abraham Mathew, J. 1. This appeal is at the instance of the second defendant against whom a decree for money has been passed. The plaintiff and the first defendant are respondents 1 and 2 respectively. 2. The second respondent had in his ownership a bus. On 16.8.1989 he borrowed Rs. 1,16,000/- from the first respondent agreeing to repay it in 30 monthly instalments. The appellant is said to be the guarantor. On the allegation that he and the second respondent allegedly executed a 'hire purchase agreement' and a promissory note in favour of the first respondent and defaulted payment of the instalments, the first respondent filed the suit for recovery of Rs. 1,48,440/-. The second respondent did not contest the suit. The appellant denied execution of the agreement and the promissory note as alleged in the plaint. The lower court decreed the suit directing the appellant as well as the second respondent to pay the amount claimed by the first respondent. Aggrieved by the decree passed against him, he has filed this appeal. 3. What is stated in the plaint is that the agreement allegedly executed by the appellant and the second respondent is a 'hire purchase agreement'. The allegations in the plaint show that it is not a 'hire purchase agreement', but a loan agreement. The statement that the second respondent was the owner of the bus is sufficient to show that it is only a loan transaction. The difference between a hire purchase agreement and a loan agreement is not relevant in this case. 4. In the minutes of the lower court it is recorded that on 2.4.2001 PW1 was examined and Exts.Al to A7 marked. It is seen from its judgment that the 'hire purchase agreement1 alleged to have been executed by the appellant and the second respondent was marked Ext A7 in the evidence. The document bears the exhibit seal of the court. But it is surprising to note that this document was not tendered in evidence through PW1, the only witness examined by the 1st respondent. It is not known how it happened to be affixed with the exhibit seal. Mere affixing exhibit seal does not make a document evidence in the case. Only when it is tendered in evidence and the court receives it in evidence, it becomes part of the evidence. Marking of a document is only a ministerial act. It is not known how it happened to be affixed with the exhibit seal. Mere affixing exhibit seal does not make a document evidence in the case. Only when it is tendered in evidence and the court receives it in evidence, it becomes part of the evidence. Marking of a document is only a ministerial act. So Ext A7 which has not been made part of the evidence cannot be acted upon merely because the exhibit seal has been affixed on it. In the evidence of PW1, the first respondent, there is not even a suggestion that the appellant, or for that matter the second respondent, has executed the document. It is true that some questions regarding the document were put to the appellant, who was examined as DW1. But that is of no significance. 5. The other document allegedly executed by the appellant is Ext A1 promissory note. Its execution is specifically denied by the appellant in his written statement as well as in his evidence. The burden is on the first respondent to prove its execution by the appellant. In his examination in chief the first respondent stated that it is the defendants who have signed Ext A1 promissory note and they signed it at his office. This is only a repetition of the allegation in the plaint and is not evidence of execution of the document. Conscious of it, the learned counsel for the first respondent by asking a leading question brought out that they signed it before him. The presumption is that if the leading question had not been put, the witness would not have given that answer. The statement is not voluntary and it cannot be taken into account. Except this answer, which is only to be ignored, there is nothing in his evidence to prove execution of Ext A1 promissory note by the appellant. 6. One Sabu is said to be the scribe of Ext A1 promissory note. He was the manager of the first respondent. He has not been examined as a witness. The explanation given by the first respondent(PWl) that he was given to understand that Sabu had gone abroad is not a proper explanation. There is nothing in his testimony to show that he made any enquiry about his availability to be examined as a witness. 7. He has not been examined as a witness. The explanation given by the first respondent(PWl) that he was given to understand that Sabu had gone abroad is not a proper explanation. There is nothing in his testimony to show that he made any enquiry about his availability to be examined as a witness. 7. The observation of the learned Sub Judge that "from the evidence as a whole there seems to be no reason to discard the plaintiff's contention" cannot be justified. 8. The lower court also acted upon the report of one Sukumara Chettiyar to prove that the appellant has signed Ext A1 promissory note and the 'hire purchase agreement'. For the reason that Ext.A7 has not been made part of evidence in the case the opinion of Sukumara Chettiyar with regard to that document does not require consideration. 9. The opinion of an expert is relevant under Section 45 of the Evidence Act. Section 75(e) read with Order 26 Rule 10A of the Code of Civil Procedure empowers the court to appoint commissioners to hold scientific investigation. By virtue of Order 26 Rule 10A (2) Code of Civil Procedure the provisions of Rule 10 of Order 26 applies to such reports. The report along with the opinion is part of the records of the case. In other words, examination of the expert is not necessary to act upon it. (Kerala State Housing Board v.Reghunadhan 1988(2)KLT 331 and Satheesh Kumar v. Special Tahsildar 2000(1)KLT 416). But its probative value depends on its intrinsic worth and not on the provisions in the Code of Civil Procedure. 10. We have perused records of the case. How Sukumara Chettiyar happened to send the report to the court is very relevant. In the cross-examination of the appellant(DWl) he was asked whether he was ready to send the disputed documents to a handwriting expert. He expressed his willingness to do so. This was in spite of the fact that the burden was on the first respondent to prove the genuineness of the document. The first respondent filed I.A. 1148/2001 to send the disputed documents to a handwriting expert. The court ordered to send the documents to Central Laboratory, Hyderabad. Thereafter, the court accepted the suggestion of the first respondent's counsel that the document might be sent to a private expert to avoid inordinate delay. He also suggested the name of one K.Khan Sahib. 11. The court ordered to send the documents to Central Laboratory, Hyderabad. Thereafter, the court accepted the suggestion of the first respondent's counsel that the document might be sent to a private expert to avoid inordinate delay. He also suggested the name of one K.Khan Sahib. 11. After hearing both sides the court sent the documents to K.Khan Sahib, who in turn, sent a letter to the court informing that he is only a finger print expert and he is not competent to examine handwriting. 12. Khan Sahib wrote to the court: "I can arrange furnishing Expert Opinion on Hand writing/signature by graphologist Sri. V.Sukumara Chettiyar through the Registered Company, Eagle Eye High tech Investigators (P) Ltd., a newly formed high level Investigative Team of several retired experts and technical personalities. What happened next is seen from the minutes the lower court recorded on 6.8.2003: "For expeditious proceedings and in the interest of justice it is hereby ordered that the request by K.Khan Sahib as per the letter is allowed". The court apparently informed Khan Sahib of its decision. Khan Sahib got the documents examined by Sukumara Chettiyar, who returned the documents to Khan Sahib along with his opinion. Khan Sahib forwarded the documents and the opinion to the court. 13. When the court passed the order to get the documents examined by Sukumara Chettiyar as suggested by Khan Sahib, there was no material before it to ascertain whether Sukumara Chettiyar was an expert. His academic qualifications were not known. 14. Experts are persons who have special or peculiar skill which is acquired by study of scientific work and practical observations. An expert is one who has made the subject upon which he speaks a matter of particular study, practice or observation; and he must have special knowledge of the subject (State of H.P v. Jai Lai & others (1999)7 SCC 280 ). He is a person instructed by experience (Narayana Kekunnaya v. Vishnu Derinjathaya- 1961 KLT 960 ). His opinion must be based on specialized knowledge. There are certain tests to ascertain the reliability of experts. His educational background, readiness to give the details of his technics and procedures are two of such tests. The lower court had no materials before it to ascertain the qualifications and competence of Sukumara Chettiyar. His opinion must be based on specialized knowledge. There are certain tests to ascertain the reliability of experts. His educational background, readiness to give the details of his technics and procedures are two of such tests. The lower court had no materials before it to ascertain the qualifications and competence of Sukumara Chettiyar. (The report shows that Sukumara Chettiyar is a retired Joint Director and Head of Documents Division of the Kerala State Forensic Science Laboratory). It is also not known whether Sukumara Chettiyar had any equipment to scientifically examine documents. Before a document is sent to a person for scientific examination the court should at least prima facie satisfy itself about his academic qualifications and competence and that he has a sufficiently equipped laboratory. This was not done in this case. When an expert is appointed to do some scientific work, it is proper that the court issues a commission warrant as provided in Order 26 Rule 10 of the Code of Civil Procedure Code. The age of handwriting expert also is relevant because he is required to have a 'photographic eye' to recognise similarities and differences in the questioned and the admitted or proved signatures. 15. An expert opinion has two parts, data part and opinion part. The opinion part is useless without data part. The opinion should be supported by reasons. Presently we shall examine whether the opinion of Sukumara Chettiyar is supported by reasons. 16. In his report Sukumara Chettiyar claims to have made a study and comparison of the questioned and the standard signatures. His report says that there are some similarities between the questioned and the standard signatures but at the same time some dissimilarities also, which he calls divergent writing habits. On the basis of the fact that there was a time gap of six years between the questioned and standard signatures he is of the view that that must be the reason for the divergent writing habits seen in the questioned signatures. He took the view that the similarities outweigh the divergences and has expressed the final opinion that the author of the standard signatures probably also wrote the questioned signatures. 17. The report does not disclose how Sukumara Chettiyar compared the signatures; nor does it reveal that he used any scientific Equipments for the comparison. He took the view that the similarities outweigh the divergences and has expressed the final opinion that the author of the standard signatures probably also wrote the questioned signatures. 17. The report does not disclose how Sukumara Chettiyar compared the signatures; nor does it reveal that he used any scientific Equipments for the comparison. He has noted all the similarities, but not even a single dissimilarity, for which there is no reason. This makes his report a lopsided one. Usually experts forward to the court enlarged photographs of the signatures along with their report. That also has not been done in this case. 18. In the light of the discussion made above, we are of the definite opinion that the lower court went wrong in acting upon the report of Sukumara Chettiyar. 19. Assuming that the opinion of Sukumara Chettiyar is an acceptable evidence under Order 26 Rule 10A CPC, we shall consider its probative value. In Ramachandra v. State of Uttar Pradesh ( AIR 1957 SC 381 ) the apex court has observed that normally it is not safe to treat expert evidence as to handwriting as a substantive piece of evidence. It is a rule of prudence that unless it is corroborated either by clear direct evidence or by circumstantial evidence the opinion of a handwriting expert cannot be acted upon (Shahshi Kumar Banerji v. Subodh Kumar Banerjee ( AIR 1964 SC 529 ). The acceptability of the opinion of handwriting experts was considered by the Supreme Court in Ram Naran v. State of U.P.( AIR 1973 SC 2200 ) also. The court has observed: "The opinion of a handwriting expert given in evidence is no less fallible than any other expert opinion. But such opinion is worthy of acceptance if there is internal or external evidence relating to the writing in question supporting the expert's view. The question in each case falls for determination on the Court's appreciation of evidence." 20. In S.Gopal Reddy v. State of A.P ( AIR 1996 SC 2184 ) the Supreme Court has observed that the evidence of an expert is a rather weak type of evidence and the courts do not generally consider it as offering conclusive proof and therefore safe to rely on the source without seeking independent and reliable corroboration. In S.Gopal Reddy v. State of A.P ( AIR 1996 SC 2184 ) the Supreme Court has observed that the evidence of an expert is a rather weak type of evidence and the courts do not generally consider it as offering conclusive proof and therefore safe to rely on the source without seeking independent and reliable corroboration. So far this case is concerned there is neither direct nor circumstantial evidence to prove execution of Ext.Al promissory note by the appellant. In the absence of substantive evidence the opinion of Sukumara Chettiyar even if assumed to be acceptable cannot be acted upon. 21. The learned Sub Judge made a comparison of the disputed signatures and the signatures in the 'written statement, vakalath etc.' filed by the appellant and took the view that the appellant is the author of the disputed signatures. This also is assailed by the learned counsel for the appellant. 22. It is true that Section 73 of the Evidence Act enables a court to make a comparison of the admitted or proved signatures and the disputed signatures. In Bisseswar Poddar v.Nabadwip Chandra (AIR 1961 Calcutta 300) and Devi Prasad v. State (AIR 1967 Allahabad 64) it is observed: "the method contemplated by Section 73 of the Evidence Act can and ought to be employed by courts in order to test and find corroboration or contradiction of the opinion of the expert. The court does not, in such a case, function as a handwriting expert itself, but it acts as the authority charged with the duty of arriving at a conclusion with the aid of all the data upon the record by all legally permissible means at its command". The probative value of the opinion formed by the court on comparison of the signatures has been discussed by the apex court in The State of Gujarat v. Vinaya Chandra Chhota Lai Pathi ( AIR 1967 SC 778 ). The court has observed that comparison may be made by the court in order to appreciate properly the other evidence produced before it. The court has observed that comparison may be made by the court in order to appreciate properly the other evidence produced before it. In State v. Pali Ram ( AIR 1979 SC 14 ) the Supreme Court has administered a caution: "Although there is no legal bar to the Judge using his own eyes to compare the disputed writing with the admitted writing, even without the aid of the evidence of any handwriting expert, the Judge should, as a matter of prudence and caution, hesitate to base his finding with regard to the identity of a handwriting which forms the sheet-anchor of the prosecution case against a person accused off an offence, solely on comparison made by himself. It is therefore, not advisable that a Judge should take upon himself the task of comparing admitted writing with the disputed one to out whether the two agree with each other the prudent course is to obtain the opinion assistance of an expert." 23. The learned counsel for the first respondent reliesf on the decision of the Supreme Court in Neelalohithadasan Nadar v. George Mascrene (1999) Supp(2)SCC 619) in support of his argument that there is nothing wrong in the court's taking a decision on the basis of comparison of the signatures. That was a case in which there was an allegation of double voting and impersonation in an election. The High Court made comparison of the disputed and admitted signatures, which received the approval of the Supreme Court. But that was on the peculiar facts and in the special circumstances of the case, which is clear from the following observation of the Supreme Court: "We, however, are of the view that when larger public interest is served by expeditious disposal of an Election Petition, then the course adopted by the High Court, as suggested from the afore-extraction, is in conformity therewith. Although courts should be slow in resorting to this method, we do not find it faulted, more so when the Courts resort to exercise of such power is approved in two other cases of this Court in State (Delhi Administration) v. Pali Ram(1979(l) SCR 931) and Murari Lai v. State of Madhya Pradesh ( 1980(2) SCR 249 )". 24. But in a later decision the Supreme Court repeated the caution it had administered earlier in State v. Pali Ram (supra). 24. But in a later decision the Supreme Court repeated the caution it had administered earlier in State v. Pali Ram (supra). That also was a case under the Representation of the People Act where there was an allegation of double voting. The Apex Court held: *the caution administered by this Court as to the course to be adopted in such situations could not have been ignored unmindful of the serious repercussions arising out of the decision toi be ultimately rendered." 25. What is discernible from the above decisions is thait except in exceptional cases the court shall not rest its decision only on the comparison made by it. Ordinarily, it may be done only to appreciate the other evidence or to strengthen the view which could be taken on other substantive evidence. In the case on hand it has already been found that the opinion of the expert is mot at all satisfactory and cannot form the basis of the decision in the case. The reasons for his forming the opinion does not find a place in the judgment of the learned Sub Judge. It was the result of his subjective satisfaction only. In this regard the observation made in Thiruvengada Pillai v. Navaneethammal (2008(2) JKLT 267 (SC)) is very relevant. The Supreme Court has said: "....Further even in cases where the court is constrained to take up such comparison, it should make a thorough study, if necessary with the assistance of counsel, to ascertain the characteristics, similarities and dissimilarities. Necessarily, the judgment should contain the reasons for any conclusion based on comparison of the thumb impression, if it chooses to record a finding thereon. The court should avoid reaching conclusions based on a mere casual or routine glance or perusal." In the absence of any substantive evidence the lower court fell into error in reaching the conclusion that the comparison also proves that the appellant was the author of the disputed signatures. 26. In the light of the discussion made above, we are compelled to hold that the decree passed by the lower Court as against the appellant is liable to be set aside. In the result, this appeal is allowed. The decree of the lower court as against the appellant is set aside. No costs.