delivered the opinion of the court.
The plaintiff, a minor, purchased from defendant a lot of store fixtures, dry goods and groceries, October 1, 1886. He paid no cash but gave in payment his promissory note for $229.54, payable on or before two years after date, and secured by a chattel mortgage on the property bought. The mortgage contains the following condition:
“In case of a sale or disposal, or attempt to sell or dispose of said property, or removal- or ■ attempt to remove the same from the premises, number 3922 Sophia *163avenue, St. Louis, Missouri, or of an unreasonabe depreciation in value thereof, the said Wm. Graham may take possession,” etc.
The plaintiff thereupon began to dispose of the goods in the usual course of trade, until June 7, 1887, replenishing the stock from time to time. On the last-named day the defendant, who was landlord of the premises also, took possession of the store and its contents under the mortgage for condition broken, claiming that his security had been impaired. The plaintiff thereupon retook the property, by instituting the present action of replevin, and upon its trial recovered judgment for possession of the entire property and damages. Hence this appeal.
The chattel mortgage is in the usual form. When it was offered in evidence the defendant’s counsel claimed, that by its terms the plaintiff had no right to remove or sell any of the stock of groceries purchased by him from the premises, whereupon the court made the following ruling:
“ The construction to be put upon that chattel mortgage is, in regard to the disposition of the goods, that the purchaser cannot dispose of the whole stock in a lump, just as it was sold by Graham to Fleming. Mr. Fleming would not have the right to sell it outright and allow some one else to take it and remove it, but it would be a very strained construction to put upon a contract of that kind, that he could not be allowed to sell the kegs of beer, or any other articles in the line of groceries that were perishable until the two years were out.”
The court adhered to this ruling in its instructions to the jury, and the correctness of that view is the only substantial question presented for our consideration upon this appeal.
It is not pretended that the parties made an additional contract, either cotemporaneous or subsequent, *164affecting the defendant ’ s rights in the premises, nor is it claimed that there was a waiver of any of the conditions of the mortgage. There was no evidence whatever to support either theory. The case was tried and submitted to the jury solely upon the construction put upon the condition of the mortgage by the court, and if that construction was incorrect the judgment cannot stand.
That a written contract, plain and unambiguous, cannot be varied, explained or qualified by any testimony, and that such testimony is not admissible to overthrow the plain meaning of written terms, is fundamental law which need not be discussed. That part of the goods mortgaged were perishable can make no difference. The question is not whether the contract made by the p arties was wise or improvident; the sole question is what that contract was. That question is conclusively answered by the express terms of the contract itself. In the absence of fraud or mutual mistake, the parties are conclusively held to have meant what they said, and any evidence of intention dehors the contract is inadmissible.
Since it stands admitted that the mortgagor did sell and dispose of part of the property mortgaged, it necessarily stands admitted that the mortgagee might lawfully enter for condition broken. The disposal of the goods was also necessarily a depreciation in the value of the mortgaged property, since the mortgagee had no legal lien on the goods bought in lieu of the goods sold.
The aid of surrounding circumstances, and of the conduct of the parties, are available for purposes of construing a contract only in case of latent ambiguities in some of its terms. That proposition is fully and clearly stated in St. Louis Gas Light Co. v. City of St. Louis, 46 Mo. 121. Here are no such ambiguities.
We might add, that the construction put upon the contract by the court, is not only erroneous because a *165departure from its plain terms, but is not a whit more sensible than the construction which it seeks to avoid. If the sale provided against in the condition was a sale in lump only, the mortgagee might well sell all the property piecemeal, and thus destroy the mortgagee’s security entirely, which was clearly not within the contemplation of the parties.
As some question arises upon the record, whether or not the mortgagee took more property than was actually covered by his mortgage, and since for property thus taken, he may be held liable in this proceeding, we will remand the cause for trial.
Reversed and remanded.
Judge Biggs concurs. Judge Thompson dissents.