— This was a suit brought before a justice of the peace by plaintiff to recover of defendant the contract price for painting the roof of a house, barn and shed of the later. Defendant interposed a counterclaim.
At a trial in the circuit court where the plaintiff had judgment, from which defendant appealed, the. plaintiff, to maintain the issue in his behalf, was permitted to introduce in evidence the following writing:
“I, ~W. C. Broughton, having agreed to paint G. Null’s house and barn and sheds for which George Null agrees to pay W. C. Broughton the sum of $1.50 per square.
“[Signed] Geo. W. Null.
“Sept. 10, 1890.”
The plaintiff then introduced evidence tending to :show that he had painted the roofs of the house, barn and shed of the defendant but not the house, barn and *234shed in their entirety as stipulated in the memorandum.
The defendant offered to prove, by parol evidence, as a part of the contract, that the plaintiff came to the ■ defendant and offered to paint the roofs of the house, barn and shed of the latter with a paint that would not contain in its ingredients any coal tar; that he, plaintiff, would warrant the paint to endure on these • roofs and be water proof and that they would last for ~ ten years and preserve the roofs from decay, and that. he need not pay for the work until he had ample time • to ascertain that the paint did not contain coal tar and that the work otherwise complied with such representations and warranty; that the defendant agreed to-these terms, and plaintiff took out a memorandum book from his pocket and wrote on it the words which. is the purported contract offered in evidence, and. asked defendant to sign it as an evidence of what he. was to pay for the work; that with this agreement and understanding he then and there signed the paper' offered in evidence, and handed it to. the plaintiff. The-offer of the defendant was by the court rejected and this action of the court constitutes the defendant’s chief ground of complaint.
Written instruments executed by the parties themselves are in their very nature most trustworthy-evidence of what they have transacted. It is their-own testimony that they have furnished against themselves, and, of course, it can not be said of it, as-of a witness, that it misrepresents, either through ignorance, negligence, or design, and being permanent. and not subject of decay-like the memory of a living-witness, it continues to be a faithful memorial of the ■ transaction, no matter what length of time may since have intervened. So the rule is now well settled in. this state that if the instrument import a legal obliga-*235tion, without uncertainty as to the object and extent-of the engagement, it is conclusively presumed that the whole engagement of the parties was reduced to-writing and no contemporaneous parol evidence is admissible to change the contract, by altering or expunging any of its provisions, or by adding new ones to it.
But this rale does not apply where the writing on its face appears to be incomplete or merely a one-sided expression of the terms of the agreement. Rollins v. Claybrook, 32 Mo. 405; Moss v. Green, 41. Mo. 389; Ellis v. Bray, 79 Mo. 226; Brown v. Brown, 90 Mo. 184; Tracy v. Iron Works, 104 Mo. 193; Rucker v. Harrington, 52 Mo. App. 481.
. In cases coming within this exception' parol evidence is admissible to explain and supply the omissions. Norton v. Bohart, 105 Mo. 615.
It is not to be disputed that the writing here is imperfect, and does not contain a full expression of' all the engagements of the parties thereto. This, becomes more apparent from the fact that it is conceded by the plaintiff himself, that it was the agreement that, he only bound himself to paint the roofs of the-buildings it describes, instead of the buildings themselves in their entirety. The plaintiff was compelled at the outset to resort to parol evidence in order to make-out a prima facie case. Without this he could not show compliance on his part with the contract. But further-scrutiny of the writing will show that it was imperfect in not indicating the kind or quality of the paint nor-the number of coats thereof to be used.
These omissions appearing upon the face of the-writing, are sufficient to satisfy us that the entire-agreement of the parties in respect to the subject-matter is not to be found contained in its provisions, and therefore, under the exception which we have-*236stated, parol evidence was admissible to show the •entire agreement that was entered into. No reason is perceived why, if there was a warranty, it may not be shown by parol. It follows that the action of the trial court in rejecting the defendant’s offer of parol proof was erroneous.
As the judgment must be reversed and the cause remanded for the error already stated, we may remark that if there be another trial the instructions should be recast and made to conform to all the evidence •adduced, including the parol evidence, if again offered, which we have declared admissible. The repugnancy ■of the instructions as they stand will then appear more glaring than even now. ■ This-objection will then, no ■doubt, be obviated without further suggestion from us.
The judgment of the circuit court will be reversed and cause remanded.
All concur.