Mr. Khalid Islam one of the renowned Physcist from Pakistan held a conversation on Hijri Calender in a LinkedIn Post:
Guess the Most Stable and Predictable Calendar of the World?
Knowing my interest, Mr. J. Mac A Steele (In-charge, Time & Frequency lab at National Physical Laboratory, Teddington, Middlesex, UK) who was my very respectable supervisor, provided me a copy of an excellent article: “Making a firm date, New Scientist,25 March 1982, pp 770 by Geoffrey Thomas”. I studied it thoroughly and worked hard to convert Gregorian, Hijra Calendars and Modified Julian Day in to electronic circuits.
During my NPL’s research and development time, I knew about the algorithm of Gregorian calendar and I was searching for the algorithm of Hijra calendar. At the end of my 12 months stay at NPL, I was successful to develop a compact Time and Frequency Time Code Generator-ALM. This was capable of displaying time of the day, day of week, date on Modified Julian Day, Gregorian and Hijra Calendars etc.
The time base was the electronic pulses of “second” generated by a Cesium Atomic Time clock of NPL, stable to 412 pico-second for consecutive seconds generated from this clock. Second pulses counted to minute and hours, giving day long pulse after 24 hour which were used for counting day of the week, generating Modified Julian Day, also Gregorian and Hijra calendars etc.
A compact equipment was developed using 251 Integrated Circuits for counting and taking decisions to generate Gregorian calendar, even for 400 years leap day and 33 years cycle of changing the length of months in Hijra calendar as per algorithm pointed in this article. Mr. J.Mac A Steele and his team were extremely excited about this work.
Related: Pakistan Standard Time and the Role of Computers
In fact living in a third world country we had a little access to the printed published journals. Alas, the copy of this article was misplaced in the year 1995 during my posting and transfer from Islamabad to Lahore. I always had sorrow about this loss. A few days ago suddenly, I searched this article on Google and found it. Once again I enjoyed this article and desired to acknowledge and thank its author even after a long time.
Here is a review of what he learnt about the history of calendars (any content from the article being reproduced with permission) and which is still valid for centuries to come! Hijra calendar, without any doubt, is most accurate and highly stable calendar.
It looks as if people are happy with present day Gregorian Calendar relevant to its specific use. Likewise, Dr. Geoffery Thomas thinks and I rephrase, the logic and order of a Calendar does not always qualify the definition of a day; but suggested by the fate of the proposed World Calendar and its Revolutionary forerunner.
Mr. Khalid Islam in an interview to Titantwister.com