Malimath, CJ.

These three writ petitions are by the Assistant Engineers in the Radio branch of the Public Works Department, who have challenged the prescription of the ratio of 1:1 between graduates and non-graduates Assistant Engineers prescribed by the proviso to rule 2 of the Kerala Engineering Service (Radio and Electrical branches ) Rules, hereinafter referred to as the Rules, for promotion to the cadre of Assistant Executive Engineers (Radio). Rule 2 of the Rules which prescribes the method of appointment to the cadre of Assistant Executive Engineers (Radio) reads as follows:

"2. appointment.--(a) Appointment to the categories specified in column (2) of the Table below shall be by the method specified in the corresponding entry in column (3) thereof.

2. Assistant Executive Engineer (Radio)

1. Recruitment by transfer from category of Assistant Engineer (Radio) of the Kerala Engineering Subordinate Service (Radio branch)

2. In the absence of suitable candidates for appointment by transfer by direct recruitment.

(b) Promotion and appointment by transfer shall be made from select lists of eligible officers prepared on the basis of merit and ability, seniority being consider