The negotiations between the parties which ended in the execution of the contract and indenture appear to have commenced in January 1946. The intending lessees were then the respondent and her husband and the intending landlords the appellants. They all went to see Mr. Coy, the solicitor for the appellants, at the end of that month, and his note of the interview states that the tenant has the right to purchase the property freehold for £15,750, such option to be exercised within twelve months. Mr. Cleary, who was instructed to act for the respondent and her husband, made a note to the same effect on 8th February 1946. At the time of the negotiations the hotel was subject to a lease to one Hackwill, which was about to expire on 23rd March 1946. The hotel was in the hands of one Smythe, who died before the hearing, for sale or lease, and the plaintiff and her husband were desirous of purchasing the freehold. But in January they were unable to arrange finance, and it was for this reason that the negotiations which resulted in the contract of 12th March 1946 and indenture of lease of 28th March 1946 were for a lease of the hotel with an option of purchase. The hotel was at the time in need of repair. The outgoing tenant had deposited £500 with the appellants as security for the performance of the covenants in the lease. The appellants were willing that so much of this sum as they were able to retain as damages for breach of these covenants should be paid to the new lessee to be used towards placing the hotel in repair. It was also agreed that the rent of the new lease should be £30 a week for the last two years, but should only be £25 a week for the first year, the new lessee agreeing to expend the difference, i.e., £260 on repairs. If the intended option had been simply an option to purchase the hotel at any time in the first year, its exercise would have operated to merge the two estates in the lessee and thereby determine the lease during the year. But it is clear from the evidence that the appellants, either initially or at some early stage of the negotiations, decided that they would not give the new lessee an option which could be exercised so as to destroy the lease before the end of the first year. They wanted a full year's rent in any event, so that the option, whilst exercisable only during the first year, was not to be completed before the end of that year. It is not clear whether this proviso to the exercise of the option was disclosed to the respondent and her husband before the interview with Coy. From his diary note and that of Cleary it would appear that it was not. It is clear, however, that at the interview with Coy, there was no concluded contract between the parties. They were engaged in the preliminary negotiations and it was intended that Coy should prepare a draft contract which he should submit for approval to Cleary, and that when the solicitors had agreed upon its terms a formal contract should be engrossed and signed by the parties and this should be the commencement of their contractual relations. Coy prepared a draft agreement which was submitted to Cleary and returned by Cleary to Coy with a number of amendments. The draft agreement provided for the exercise of the option at any time after the expiry of one year from the date of possession by the lessees giving three months' notice in writing. It also provided that the purchase price should be £15,750, but should be subject to the payment in addition of the sum spent on any structural alterations which might have to be made during the term to the hotel premises to comply with certain Victorian statutes. Cleary naturally realized when he received the draft that the option was not an option exercisable during the first year but after expiry of that year and consulted his clients, who instructed him to accept the alteration rather than risk losing the hotel. Cleary made several amendments to the form of the option which made it very plain that it was only exercisable after the expiry of one year because he made it provide that the option should be exercisable after the expiry of one year from the date of possession unless the landlord had already exercised or within seven days thereafter exercised the right of re-entry under the lease. These amendments were accepted by Coy, who wrote to Cleary on 7th March 1946: "We have gone through the draft agreement with our clients and the enclosed engrossment, we think, represents the views of the parties". The engrossment became the contract of 12th March 1946, which was executed by the appellants and the respondent and her husband. There is nothing in the evidence to suggest that the respondent and her husband did not execute the contract and the subsequent indenture of lease otherwise than in the bona-fide belief that the option had been deliberately changed by Coy from an option exercisable during the first year to an option exercisable after the expiry of that year to give effect to the appellant's insistence on receiving one year's rent in any event. It would appear that Coy failed to call the attention of his clients to the manner in which he had endeavoured to give effect to their wishes and that they executed the contract and indenture without reading them, relying on Coy's assurance that they were in the proper form. Coy gave a copy of these documents to his clients and they soon discovered that the option did not give effect to their wishes. On 9th April 1946 Coy wrote to Cleary stating that what was actually agreed to by the parties was that the option had to be exercised within one year but the purchase was not to be given effect to by way of completed sale until the first year of the term of the lease had expired. His Honour found, and we accept his finding, that "it is probable that the defendants at all times believed they were contracting for an option exercisable only in the first year". The appellants were therefore mistaken as to the form of option contained in the contract and indenture. But it was a unilateral mistake not contributed to by the respondent. His Honour accepted Cleary's evidence that when discussing the draft agreement with the respondent's husband, he drew the latter's attention to the word "after" and said this is a change, to which Warke replied: "Yes they are not prepared now to sell unless they also get a year's rent in addition to the purchase money. That is why they have made this change. I think it will suit us alright. I have had so much trouble in getting finance, but we will be better off in a year or so". The mistake was therefore one for which the appellants only had themselves to blame. They placed a blind trust in their solicitor and executed the documents without having them read over. The respondent and her husband at the commencement of the negotiations appear to have had a common intention with the appellants that the option should be exercisable during the first year, but there is no evidence that the common intention ever went further and also included an intention that the option should only operate to determine the lease at the end of the year. When the new form of option was submitted to them in the draft agreement they agreed to accept it with the amendments made by Cleary. Coy accepted these amendments and expressly stated that they were acceptable to his clients. This evidence does not establish, and the appellants do not now contend, that the respondent executed the contract or indenture knowing that the option of purchase was not in the form intended by the appellants. The respondent and her husband did nothing to induce any mistaken belief in the appellants as to its form.