Appeal by plaintiff from a judgment declaring that it is its obligation to pay defendants the amount of a sales tax assessed and levied against and paid by defendants.

On October 2, 1951, defendants, as lessors, and plaintiff, as lessee, entered into a written lease of a concrete batch plant and related equipment for a term of 36 months with rental of $447.23 a month. The instrument contained this provision:

On October 9, 1951, by letter agreement, plaintiff and defendants modified the terms of the option by providing that the $2,500 should be paid within one year rather than three years and for payment of an additional $1,000. On October 1,1952, plaintiff exercised the option, paid defendants $3,500, and received the equipment.

About March 15, 1954, defendants paid the State of California $627.76 as a sales tax assessed and levied against them. The $3,500 paid by plaintiff to defendants for the equipment was utilized as the measure of the tax.

A controversy developed between plaintiff and defendants. Defendants maintained plaintiff was liable to them for the tax under the terms of the lease; plaintiff, that it was not. Plaintiff brought the action to settle the dispute.

The court found that pursuant to the lease the tax was the obligation of plaintiff and that by reason of plaintiff’s refusal to pay the amount of it to defendants, plaintiff had breached the lease and was in default. Judgment followed accordingly, together with a decree that plaintiff pay defendants’ attorney’s fees.

The question involves a construction of the lease. The trial court construed it without the aid of extrinsic evidence. A reviewing court is not bound by a trial court’s con struction of a document based solely on the terms of the written instrument without the aid of extrinsic evidence, (Estate of Platt, 21 Cal.2d 343, 352 [ 131 P.2d 825 ] ; Estate of Moody, 118 Cal.App.2d 300, 305 [ 257 P.2d 709 ].) The construction of the lease presents a question of law. (Union Nat. Bank v. Hunter, 93 Cal.App.2d 669, 673 [ 209 P.2d 621 ] ; Oberg v. City of Los Angeles, 132 Cal.App.2d 151, 153 [ 281 P.2d 591 ].)

The only pertinent provision of the lease is this:

A sales tax is an excise and privilege tax levied on a retailer for the privilege of selling tangible personal property. Section 6051 of the Bevenue and Taxation Code says:

An excise tax is imposed upon the right to exercise a privilege. (Ingels v. Riley, 5 Cal.2d 154, 159 [ 53 P.2d 939 , 103 A.L.R. 1 ].) A privilege tax is not a property tax. (Id.; Anders v. State Board of Equalization, 82 Cal.App.2d 88, 93 [ 185 P.2d 883 ].) The law imposes the fixed rate of the tax on gross receipts and not on the individual sale of tangible personal property. (Western L. Co. v. State Board of Equalization, 11 Cal.2d 156, 163 [ 78 P.2d 731 , 117 A.L.R. 838 ].) It is not a tax on the sale or because of the sale but is an excise tax for the privilege of conducting a retail business measured by the gross receipts from sales. (Id., 164, 166-167.)

It has uniformly and consistently been held that the sales tax is laid solely on the retailer and not on the consumer. The tax relationship is between the retailer only and the state; and is a direct obligation of the former. (Western L. Co. v. State Board of Equalization, supra, 11 Cal.2d 283, 289-290 ; DeAryan v. Akers, 12 Cal.2d 781, 783 [ 87 P.2d 695 ] ; Clary v. Basalt Rock Co., 99 Cal.App.2d 458 [ 222 P.2d 24 ]; Pacific Coast Eng. Co. v. State of California, 111 Cal. App.2d 31, 34 [ 244 P.2d 21 ]; General Elec. Co. v. State Board of Equalization, 111 Cal.App.2d 180 , 185 [ 244 P.2d 427 ].) A retailer may “pass on” the tax to a buyer with the latter’s consent thereto either expressly or impliedly given. Section 6052 of the Revenue and Taxation Code provides:

Pacific Coast Eng. Co. v. State of California, supra, 111 Cal.App.2d 31 , involved the right of a seller of personal property to collect sales taxes from the buyer. The plaintiff sold dump scows to the state under a written contract which specified the price of each scow but was silent on the subject of sales tax. The state refused to pay the tax added by the plaintiff to the contract price, and the plaintiff sued. The court held (p. 33):

In Clary v. Basalt Rock Co., 99 Cal.App.2d 458 [ 222 P.2d 24 ], the court said (p. 461):

Applying the foregoing principles to the case at bar it'is manifest that plaintiff is not obligated to pay the sales tax and that the court erred in so declaring. Defendants were retailers. (Rev. & Tax. Code, § 6015.) On making the sale they, and they only, were liable to the state for the tax. The obligation was theirs, not plaintiff’s. They could have passed the tax on to plaintiff by so providing in the lease but they did not do so. Plaintiff did not agree to pay the tax. It did not do so in the purchase option provision, which was the only part of the contract fixing the terms of sale of the equipment. The provision that the lessee, plaintiff, shall “pay all costs and expenses of every character occasioned by or arising out of such use, and pay promptly when due all taxes and other public charges against or upon the equipment” is not a term of the option; it is a term of the lease. It occurs between a paragraph requiring the lessee to keep the property insured and one declaring that all the equipment shall remain the property of the lessor exclusively. The option is the last paragraph of the instrument; it follows the agreements which constitute the lease. The costs and expenses mentioned are those occasioned by or arising out of the use of the leased property by the lessee, as lessee, during the term of the lease. Taxes against and upon the equipment are personal property taxes, not excise taxes imposed on defendants for the privilege of selling tangible personal property. Plaintiff clearly and explicitly agreed to pay personal property taxes on the equipment during the term of the lease, nothing more. It did not agree to pay a privilege tax assessed against defendants on the sale of the equipment any more than it agreed to pay an income tax assessed against defendants, or a license tax, or a gross receipts tax.

Third & Broadway Bldg. Co. v. Southern Calif. Edison Co., 132 Cal.App. 186 [ 22 P.2d 574 ], is in point. The court said (p. 190) :

The canon of construction which teaches that the function of a court in construing a written instrument is to ascertain—neither to add nor to subtract, neither to delete nor to distort—applies. No more need be said than that to vary the terms of the instrument' so as to make it mean what defendants contend and the trial court held it means would be to make a contract the parties did not enter into. That the courts cannot do. Defendants did not pass the sales tax on to plaintiff and plaintiff did not expressly or impliedly consent thereto and is not liable therefor.

Reversed.

Shinn, P. J., and Wood (Parker), J., concurred.