Tag Archives: longitude

Five and a half hours ahead of Greenwich Mean Time (GMT): India

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INDIA IS A very large country. At its greatest width, it spans almost 1800 miles from east (the Manipur/Bangladesh border) to the west (the western edge of Kutch where it borders Pakistan.). When it is 4 am (GMT) in London, 1500 miles away in Moscow (Russia) and 1800 miles away in Ankara (Turkey), it is 7 am.   Yet, when the sun rises at 4 am in the far east of India, people in Kutch (western Gujarat) will not see the sun rise until 5.30 am. In both places, the clock will show ‘4 am’. This difference arises because all of India (as well as Bangladesh and Sri Lanka) are in the same time zone (Indian Standard Time: ‘IST’). IST is five and a half hours ahead of Greenwich Mean Time (‘GMT’). Incidentally, while researching this piece, I noticed that clocks in Nepal are 5 ¾ hours ahead of GMT.

Some countries spanning many degrees of longitude such as India does, are divided into several time zones (e.g. the USA, the Democratic Republic of the Congo, and Russia). However, all of India is in a single time zone, I wondered why and whose idea it was in the first place.

Prior to the colonisation of India by the British, various methods of standardising time were adopted in different eras and under varying ruling regimes. For example, in the 4th century BC, the prime meridian was chosen as a line passing through what is now the modern town of Ujjain (in Madhya Pradesh) and the unit of time was based on the ‘prana’ (about 4 seconds – the length of a normal breath).

In 1802, John Goldingham, the official astronomer of the British East India Company, established Madras Time, which was 5 hours, 21 minutes and 14 seconds ahead of GMT. In 1884, Calcutta Standard Time was established. This was 5 hours, 53 minutes and 20 seconds ahead of GMT. It remained in use until 1948 despite other changes in time zoning having already occurred in India. At the same time as Calcutta Standard Time was created, Bombay Standard Time also came into existence – it was 4 hours and 51 minutes ahead of GMT. Although it no longer exists, it is still used in Parsi fire temples in Bombay.

Madras Time was used by the railways in British India until the 1st of January 1906, when IST came into existence. It was then that the geographical reference point for time standardisation was moved from Madras to Shankargarh Fort in the district of Allahabad. The reference meridian chosen, 82 degrees and 30 seconds East, was deemed to be the midpoint of India, as it was under British rule. In 1947, when India became independent, IST was kept as the country’s official time. However, both Calcutta Time and Bombay Time remained in use until 1948 and 1955 respectively. The idea of splitting India into two time zones has been mooted, but has yet to happen.

Although IST is the official time in all parts of India, an interesting variation is still in use in the tea gardens in the far east of the country (www.timeanddate.com/time/zone/india). Called ‘Chai Bagan Time (Tea Garden Time), it is one hour ahead of IST (and 6 ½ hours ahead of GMT). It was introduced by British tea companies to increase the number of daylight hours available for working, and is still in use. Using this timing, the sun rises at 5 in the morning instead of at 4 (IST) and sets at about 6 in the evening instead of 5 (IST).

Bombay Time has all but disappeared from use. However, it has been replaced by what some call ‘Bombay timing’, which refers to the habit of people to arrive incredibly late for appointments – especially social engagements. Finally, in a book about Bangalore by Peter Colaco, there is mention of yet another measure of time. There is ‘fie-mint’, which does not mean ‘five minutes’, but does mean ‘not very soon’. For example, he wrote:

“A waiter in a restaurant, once told me our order would take ‘fie-mint’. Did he mean a ‘five minute ‘fie-mint’ or a 30-minute ‘fie-mint’, I asked. He considered the question seriously. ‘Twenty-mint fie-mint’, he clarified.”

It was much earlier than Greenwich Mean Time

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DESIGNED BY BENJAMIN Wyatt (1775-1852) and George Louch, then later modified by John Rennie (1761-1821), The Clock House (built 1817) overlooks the harbour in Ramsgate, Kent. As its name suggests, this building is surmounted by a square tower with clocks on each of its four sides. Today, the time on the clocks is Greenwich Mean Time (‘GMT’) or, when appropriate, British Summer Time (GMT+1). But this has not always been the case.

The Clock House was home to chronometers that were used to synchronise shipborne chronometers employed for determining longitude. The edifice stood on what was known as the Ramsgate Meridian Line, which was established in 1819. This was before 1851 when Sir George Airy (1801-1892) defined the position of the prime meridian that runs through the observatory at Greenwich. It was not until 1884 that the prime meridian at Greenwich was recognised internationally, much to the disgust of the French, who hoped it would run through Paris.

The now disused Ramsgate Meridian Line is east of the Greenwich prime meridian. So, when the clocks on the Clock House were set to Ramsgate Mean time, they were 5 minutes and 41 seconds ahead of GMT. A notice beneath the clock tower informs the viewer that the clocks are now set to show the same time as it is in Greenwich. And if there are any ancient mariners still using Ramsgate Mean Time, they are informed by another notice that:

“Ramsgate Mean Time is 5 min 41 sec faster than this clock.”

Whichever time you choose to use, it is well worth spending some hours, if not longer, in Ramsgate, which is full of interesting things to see as well as the Clock House.

Hampstead lies slightly west of the Greenwich Meridian

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ST JOHNS CHURCH in Hampstead’s Church Row lies 0.1811 degrees west of the Greenwich Meridian. Its longitude is 0.1811 W. This fact is unimportant to most people living in the area because Hampstead is high above sea level. However, an accurate measurement of longitude (and latitude) is extremely important to seafarers.

Tomb of the Harrison family in Hampstead

I am no expert in navigation, so please excuse me if the following explanation seems oversimplified. Latitude can be assessed measuring the positions of fixed astronomical objects such as the sun and the North Star and relating them to the horizon. Longitude proved far harder to measure because it involves relating the local time to the time at a reference position, now at the commonly accepted Greenwich Meridian.  The difference in the time at a position in the sea and that at Greenwich is the way that the calculation of longitude is made. Local time can be measured by means such as observing where the sun appears in the sky. Until the 18th century, no clocks existed that could reliably record the time at the reference position whilst at sea. The uncertainty involved in assessing longitude resulted in many unfortunate disasters at sea. In 1714, the British Parliament passed the Longitude Act of 1714, which offered prizes for a simple and practical method of assessing longitude out at sea.

To solve the problem, a clock that accurately recorded the time at Greenwich was required. This clock had to remain accurate despite the many changes that it would encounter as it moved across the seas. It had to record Greenwich Mean Time accurately and reliably despite changes in temperature, humidity, air pressure, motion of the vessel, and so on. Major advances in the solution of this demanding technical problem were made by a carpenter and clockmaker John Harrison (1693-1776), who was born near Wakefield in Yorkshire. For over 40 years, he worked on the problem, producing ever more reliable chronometers, which were tested at sea. Eventually, his H4 design became the prototype for what was best suited to the job. With the help of his son William Harrison (1728-1815), Harrison was rewarded with much of the financial reward offered in the wording of the Act passed in 1714.

When he died, John Harrison was living at his home in Red Lion Square in Holborn, whose longitude is 0.1186 W. He is buried in the same churchyard as the great artist John Constable: in the cemetery next to St Johns Church in Church Row, Hampstead. His tomb, which close to the south wall of the church, is of Portland stone and decorated with pilasters in the style of the architect Robert Adam. The north side of this shoebox shaped monument has an inscription that gives a brief biography of John Harrison. His wife, Elizabeth, who died in 1777, aged 72, is also commemorated on this tomb. The south side gives a short biography of his son William, who is also buried here. In addition to helping his father test his chronometer, he was also a Governor of the Foundling Hospital in London and High Sheriff of Monmouthshire (in 1791).

According to Christopher Wade in his “Buried in Hampstead”, several persons, who were not resident in Hampstead were interred in the churchyard of St John. The Harrisons figure amongst these. Wade states that there is no evidence that John Harrison and his family had any connection with Hampstead. He speculates that they obtained a burial plot there because they were “… affected by the charm of this particular graveyard.”  

The graveyard still retains its charm. It contains the resting places of many people, who have achieved fame in diverse fields of activity. Some of them are mentioned in my new book about Hampstead, which is available as a paperback from Amazon (https://www.amazon.co.uk/dp/B09R2WRK92) and as a Kindle e-book.

John Constable and a bookseller’s grave

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ST JOHN’S IS the parish church for the C of E parish of Hampstead. The present building, designed by Henry Flitcroft and John Sanderson, was dedicated in 1747. It stands on Church Row, which is lined with elegant 18th century houses and links Heath Street with Frognal.

Church Row, Hampstead, London

The church is at the northern edge of a graveyard well populated with funerary monuments, including the grave of the artist John Constable (1776-1837). This grave is in the old part of the church’s cemetery, which was hardly used after 1878, when it was officially closed. A larger, newer graveyard is on a sloping plot across Church Row and north of St John’s. This is the burial place for a host of well-known people as well as the family of Hampstead’s Pearly Kings and Queens.  

When I used to visit Hampstead in the 1960s and early 1970s, I used to ‘haunt’ a most wonderful second-hand bookshop on Perrins Lane, which leads east from Heath Street. It was owned by an old gentleman, whose name, Francis Norman, I only learnt many years after he died. Recently, I met a member of Mr Norman’s family. He told me that Mr Norman died in 1983 and is buried in the cemetery at St Johns, describing the location as: “by a wall near Harrison and the children’s playground”.

I was not sure to whom he was referring when he mentioned “Harrison”. At the church, we asked a lady about Mr Norman’s grave.  Hearing that he had died in 1983, she suggested that we looked in the newer part of the cemetery. This has a wall that borders a children’s playground. When I looked around carefully, I found  neither any monument to Harrison nor Norman’s gravestone.

On returning to the church and explaining our unsuccessful quest, the lady sent me to see another church official, who was working in an office attached to the church. This lady knew exactly where Mr Norman was buried. She took me into the older part of the cemetery and showed me the gravestones of Francis and his wife Sonia, which lie next to each other. They are next to a small wall and close to a large monument to the clockmaker John Harrison (1693-1776). He was the inventor of a marine chronometer, which solved the problem of how to ascertain longitude whilst at sea. His story can be read in “Longitude” by Davina Sobell.  Norman’s grave is not far from that of John Constable.

Francis and Sonia Norman are amongst the few people buried in the old cemetery after it was closed in 1878.  My helpful informant at the church did not know why they had been interred there instead of in the newer part.

Francis Norman was a kindly, wise, and friendly fellow, who did not mind me and several of my friends spending hours in his shop, often spending very little on his extremely reasonably priced books. I have fond memories of the time that we spent in his presence, which are described in my book “Beneath a Wide Sky: Hampstead and its Environs” (https://www.amazon.co.uk/dp/B09R2WRK92).  So, it was with great pleasure that I met one of his family and was able to pay my respects at his grave.