Search for ships by port rotation number


Ships by port rotation number

From 1835 onwards, the Registrar General of Shipping and Seamen kept registers of the service of British seamen, showing the ships they worked on and in what capacity. The registers are now held at The National Archives (TNA) in various series of records, such as BT 112, BT 113 and BT 124. The registers were made up from the crew lists and agreements. Masters of ships were legally required to keep these documents and they were returned at the end of each voyage or six monthly. The seamens' register entries were cross-referenced to the documents they came from.

Port rotation numbers formed part of a code which was used in the registers of seafarers in the period 1845 to 1854 (series BT 113), but also in other registers too. Together with the port number, they made a cross reference to the ship which the seafarer had worked on and the ship's port of registry. The key to the port numbers is known but, until now, there was no key to the port rotation numbers, so there was no easy way of tracing back to the crew lists and agreements for the ship.

The crew lists are held at TNA in the series BT 98 in thousands of boxes (pieces) sorted by year, by port of registry and then by ship's name. Even knowing the year and port, there might be many pieces to search through, each holding up to 100 documents for many different ships.

This search form provides the solution. Working from the port rotation number, it returns the ship's name and details together with a list of the boxes of crew lists in BT 98 which are likely to hold the crew documents for that ship.

Once the correct document has been found, the matching port rotation number is shown on it, thus completing the loop.

The example below shows how it works.

An example

The figure shows the register entries in BT 113/208 for an apprentice, James Breckon of Goathland (which is just inland from Whitby). He was apprenticed in 1851.

The record shows a port number of 104 which means that the ship he sailed on was registered in Whitby. The port rotation number, 86, shows the ship. Her name is not recorded, but the entries show that James worked on the same ship from 1851 to 1853 because the same port rotation number appears in each year.

The voyages in 1851 and 1852 were in the home trade (around the British Isles and the continent from the River Elbe to Brest) because the entries cover both columns. Those for 1851 cover two half years ending June 1851 and December 1851, but there is only one list for 1852.

The record for 1853 shows a foreign trade voyage. The ship is the same - 86.104.1 (it's not clear what the 1 refers to). The voyage is shown on the row below. She sailed from Woodbridge (port number 107) on 17 September 1853 and is shown arriving back on 9 September (which is probably a clerical error).

There is nothing to indicate the ship's name, so finding her crew documents could be difficult. There are ten boxes of documents for Whitby for 1853, references BT 98/3601 to BT 98/3610. Each of them contains up to a hundred documents for different ships. Knowing the ship's name would narrow the search down to just one of those boxes.

Using the search form, the results show that the port rotation number 86 refers to a ship named Concord registered at Whiby, 6/1837, 189 tons.

The results also show that the crew lists for 1851 will be found in BT 98/2778, covering Whitby B-C. We are sure about that, because that is where our data came from.

The results also show where crew documents will probably be found for other years, for example in piece BT 98/3603 which covers Whitby CI-D for 1853.

The crew lists and agreements would show some details of the voyages and an example is shown below - a foreign-going voyage to Cronstadt in July 1851 (which is not listed in James's records). Newspapers can also be used - for example, the Concord is reported as arriving in Gothenburg from Woodbridge on 25 September 1853.

Fig 1: Register of seamen entry for James Breckon in BT 113/208
Fig 2: Crew agreement for the Concord of Whitby in 1851 - port rotation number (86) and port number (104) written on the right
Fig 3: James Breckon is shown as one of the apprentices

Using the port rotation numbers search form

Enter the ship's port rotation number and select the port number from one of the drop-down lists. Then click 'Search'.

The results show the ship's name and any data which has been extracted from BT 98 for that ship, combined with information from BT 162/19 to provide details like registration entries and tonnages. We show the source of the data and if the main source is BT 98, we provide a link to TNA's Discovery.

Some data not found in BT 98 has been deduced from missing numbers. For example, if port rotation numbers 195 and 199 for Whitby match with register entries 25/1840 and 29/1840, then port rotation number 197 would match with 27/1840, which can be identified from BT 162/19 as the ship Henry. We show the source of that data as 'Deduced from BT 98 and BT 162/19'

We also provide links to the CLIP data for ships of that name, but please bear in mind that most of our data is for later years, so this particular ship may not be included.

There is also an external link to images of Lloyd's Register for 1851 on the Internet Archives site. Remember many smaller ships were not registered at Lloyd's.

Finding the crew documents

Knowing the name of the ship, it is possible to work out which boxes for other years might contain documents for the ship.

We use a colour code to show how sure we are that documents will be found, as shown in the table.

Please be aware that apart from years from which data has been extracted, there is no guarantee that documents will be found in any box, especially so where we have deduced the ship's name from other data. For some years, we can be fairly sure that the documents are not in that box, because they were not found there when data was extracted. We can not accept liability for the results of any inaccuracy in our data.

Please remember also that the data refers to the port rotation number - not to the ship's name. For example, if the ship was re-registered at the same port, there may well be documents for her after that date, but with a different port rotation number.

Where we have details of when the ship's registration at that port began and/or ended, we have used that add comments about the years for which there are likely to be documents. For example, if the ship is shown in BT 162/19 as being re-registered in 1850, we will point out that there may be records for her in later years, but with a different port rotation number.

Colour codes for crew list sources
Documents have been found in this reference
Documents may be found in this reference
Documents were not found in this reference for port rotation number nnn
Documents will probably not be found in this reference for port rotation number nnn

There are two link icon buttons against each data item for the document sources:

View TNA catalogue entry  Provides a link to the entry for this piece in TNA's catalogue Discovery.

View Family Search film  Provides a link to the images for that reference on the FamilySearch site. NB. You need an account with FamilySearch for this to work, and be working from an LDS Church Family History Centre or an affiliated library.

against a references indicates that crew name data from that reference is included in the name index (£) for the 1851 records in BT98 made by Family History Indexes

Why does a search for a port rotation number fail?

At the moment, it is simply because we have only limited data from a small number of ports.

Even for those ports, we have only a sample of the data, covering probably about 60% of the ships which were afloat in the period 1845 to 1855.

We will be adding data where we can.

Finding the key to the port rotation numbers

The key to the port rotation numbers was suggested by Peter Hamersley. CLIP has worked with him to develop the idea and extract enough data from BT 98 documents to make this search page work.

Peter Hamersley's idea was that the port rotation number was allocated to a particular ship and remained so. He had extracted all the port rotation numbers from some boxes of BT 98. We checked that data against the returns of shipping registrations which the ports of registry sent to the Registrar General of Shipping and Seamen and which are now held at TNA in BT 162/19.

The port rotation numbers were indeed allocated to individual ships and in a sequence that tied in with the shipping registrations. That allowed us to check and enhance the data and, as a bonus, allowed us to deduce some missing port rotation numbers by checking back to the sequence from the shipping returns.

For full details of how we have found and extracted the key to the port rotation numbers, please follow this link: Port Rotation Numbers


This data and the whole 1851 Port Rotation Number Project derives from the ideas and initiative of Peter Hamersley. He has backed that up by the hard slog of extracting the data which makes it all work.

We have been delighted to work with him in developing what is a major step forward in researching the crew documents held in BT 98.

Please chose the port number or port name

Port number :   

Port name :    

This is an on-going project and we are adding data steadily.

Click here to see a list of the port we have covered so far:

The table shows a list of the ports for which we have gathered port rotation number data. These are the columns:

the name of the port;
Port reference number
the reference number for that port, as used with the port rotation numbers;
PR numbers count
the count of port rotation numbers that we have found or deduced;
PR numbers max
the highest port rotation number we have found;
the percentage of the port rotation number which we have found, based on the previous numbers.
Port Port reference number PR numbers count PR numbers max %age
ARUNDEL 4 5311147
BARNSTAPLE 8 9719350
BEAUMARIS 9 23060338
DERBYHAVEN 148 4515828
DOUGLAS 147 9317553
DOVER 33 5521625
DUNDALK 37 296246
FALMOUTH 40 11023946
FAVERSHAM 41 21651741
FLEETWOOD 126 242788
FOLKESTONE 123 81553
FOWEY 42 13021660
GALWAY 43 216532
PENZANCE 77 8318544
PLYMOUTH 78 12210
PORTSMOUTH 80 23962838
RAMSEY 150 4127115
RAMSGATE 82 12432438
ROCHESTER 83 31963450
RUNCORN 120 546385
SCARBOROUGH 85 17634850
STOCKTON 93 18964229
TRALEE 119 31717
TRURO 97 398346
WHITBY 104 46678859