SETHURAMAN, J.

These two tax Revision cases arise out of sales-tax assessments for the asst. yrs. 1958-59 and 1961-62. The assessee is a company carrying on business as electrical engineers and contractors. In the assessment for 1958-59 it was claimed that a sum of Rs. 11, 96, 914.72 represented lump sum works contract executed by them for their customers. The assessee entered into agreements for execution of contracts for electrical installations in business and other premises. It appears that initially when the customer approached the assessee for execution of any such contract, it ascertained the customer's requirement by making visits to the work site and studying plan lay-out technical consultants' views, availability of power, future expansion., discussion with architects, civil Engineers, plant Engineers and other allied services. A blue print and lay out was then prepared and got approved by the electric supply authorities. The company has its own staff for watch and ward at the site and also for the execution of the work in the shape of technical and other personnel. The materials were gathered and stored in the respective premises and the erection was commenced