payable as follows viz. 2 two hundred and fifty dollars in two years two hundred and fifty dollars in three years from this date but if the building above named and hereinafter specified is Erected in manner and form following viz. a city hall for city legislation at least forty feet square and two stories high above ground of good materials and workmanship and suitable hight on the above named lot When the first story is completed said relinquishes his claim on the first payment and is to give up the note as being fully liquidated if said work is done within two years from this date and when said building is completed and finished suitable for the purposes herein named if done within three years from this date then said relinquishes his claim on the last payment and gives up said note as being canceled & liquidated and binds himself his heirs Executors and administrators to make a good and warranted deed of the above described premises to the corporation of or otherwise its legally authorized agent But if said building is not completed in time and manner above specified then [p. [2]]