HMS Mortar was a Bomb Vessel of the Infernal Class, built under Navy Board contract by Richard Wells at his shipyard at Deptford, at the time within the County of Kent, on the south bank of the River Thames.
The Infernal Class was a group of seven Bomb Vessels designed by Sir Thomas Slade, Co-Surveyor of the Navy, of which three were built in Kent shipyards. Of the other two Kent-built vessels of the class, HMS Basilisk was built alongside HMS Mortar and HMS Thunder was built at John Henniker's shipyard in Chatham. The most famous member of the Infernal class was HMS Carcass, built in Rotherhithe a little further up the River Thames in what was then the County of Surrey, in which a young Mr Midshipman Horatio Nelson served during a voyage of polar exploration. For this voyage, HMS Carcass would have had her mortars and their beds removed and would have been re-rigged with a ship rig ie. three masts, with extra accomodation provided for a larger crew. This conversion was done with all Bomb Vessels which were converted to the polar exploration role in peacetime.
A Bomb Vessel was a small vessel designed to carry one or two large calibre mortars. Mortars have been around virtually since the invention of large calibre artillery and the first recorded use of a Bomb Vessel occurred as far back as 1347. The classic Bomb Vessel first appeared in the late 1600's and were designed for the French Navy by Bernard Renau d'Elicigaray. His designs were quickly copied for the Royal Navy and were refined by designs brought over by French Protestant or Huguenot refugees fleeing persecution in France. Until the advent of the Bomb Vessel, naval artillery was pretty much ineffective against fortified positions ashore. The mortars fired a large hollow iron sphere filled with gunpowder and detonated by a fuse, timed to explode on or shortly after impact.
Although small, Bomb Vessels were massively built, using frame timbers of a size usually found in a ship of the line. They were required to be hugely strong in order to absorb the enormous recoil forces of the mortars they carried. An unintended consequence of this strength was that in peacetime, bomb vessels proved to be perfect for polar exploration, being able to better resist the pressure of being trapped in ice. Early Bomb Vessels, including HMS Mortar, were ketch-rigged, or fitted with two masts, a main mast in front of a smaller mizzen mast, in order to give a clear field of fire forward for the mortars. The mortars themselves were fixed to fire dead ahead and the range was adjusted by varying the gunpowder charge used to fire the explosive shells from the mortars. The shells or bombs themselves were detonated using a fuse which was lit immediately before firing and timed to explode at about the time of impact with the target. This meant that the Ketch-Rig was a necessary evil. Square-rigged Ketches like HMS Mortar were slow, cumbersome and difficult to handle, which is why that arrangement of sails and masts was only used for Bomb-Vessels. Later Bomb Vessels carried their mortars on traversing mounts, which enabled them to be ship-rigged, with three masts and thus easier to handle and more manoeuvrable, although still slow and heavy for a vessel of that size.
The scale of the reinforcement of the vessel's frame also meant that internal space within the hull was very limited, even more so than on a normal vessel. This meant that in addition to being very cramped internally, there was no space to carry the bombs themselves. In addition to this, bombs required very careful handling and storage, so Bomb Vessels were always accompanied by a Tender, usually a small cargo vessel chartered for the purpose.
Bomb Vessels tended to have dramatic sounding names associated with hellfire and destruction, names which reflected their role. Because of the limited scope for their use, purpose-built Bomb Vessels were very few and far between in the Royal Navy. When large numbers of them were needed in a hurry, the Royal Navy would convert sloops or gun-brigs into Bomb Vessels by fitting them with mortars and the reinforcement needed under the mortar-beds. Once finished with, a sloop or gun-brig would quickly be converted back to her original role as they were structurally unable to withstand prolonged use as a Bomb Vessel.
Because a bomb vessel was unrated, that is, she carried less than the 20 guns required to be rated, she was commanded by an officer with the substantive rank of Lieutenant who was appointed as her Master and Commander. This was abbreviated to Commander, although the formal rank of Commander did not yet exist as it does today. If an officer in the position of Master and Commander proved himself a competent commander, he would be 'posted' or promoted to Captain and appointed to command a rated vessel. If he was unlucky or not well connected enough to receive another command appointment whenever a war ended, he would revert to his substantive rank of Lieutenant and be laid off on half pay accordingly.
The contracts for the construction of both HMS Mortar and HMS Basilisk were signed on 21st September 1758. At the time, what is now known as the Seven Years War was at it's height. It had started as what is now known as the French and Indian War in the summer of 1754 when fighting broke out in the Ohio Territory between rival French and British colonists and had escalated to the point where the British had declared war against France on 17th May 1756, becoming the Seven Years War. The opening battles of the Seven Years War had gone badly for the British. The island of Minorca with the vital naval base at Port Mahon had been lost in June of 1756, it had gone badly ashore in America after the French managed to persuade many Native American nations to fight alongside them and in Europe, the main British ally Austria had allied herself with the French. Things weren't helped by political instability at home. This changed in June of 1757 when a coalition was formed between two former political opponents, the Duke of Newcastle and William Pitt the Elder. Once a division of political responsibilities had been agreed between the two men, the Government was able to set a strategic policy which had been lacking before. In 1758, Pitt decided on a strategy to distract the French by attacking them in their overseas possessions. This approach had a number of advantages. Firstly, it would divide the French forces by making them send troops and ships to defend their colonies and trading posts and secondly it would deprive the French of trade and therefore money. A series of so-called 'Descents' or amphibious assaults were launched on the French coast, their trading posts on the west coast of Africa and in the West Indies were attacked and taken and plans were laid to take Quebec. Orders were placed in the autumn of 1758 for Bomb Vessels, including HMS Mortar as part of this overall strategy.
The first elm keel section of what was to become HMS Mortar was laid on the same day as that of her sister-vessel HMS Basilisk, on the 2nd October 1758. Construction proceeded rapidly and the completed hull was launched into the River Thames on the 14th March 1759. After launch, HMS Mortar was taken to the Royal Dockyard at Deptford to be fitted with her mortars, guns, masts, rigging and sails. On the 18th June 1759, Mr Joseph Hunt was appointed Master and Commander with orders to oversee the completion of fitting the vessel out and prepare her for sea service, recruit a crew and commission HMS Mortar for service with the Channel Fleet.
Joseph Hunt had been born in 1733 and first entered the Royal Navy at the age of eight in 1741. He passed his Examination for Lieutenant on the 1st May 1754 and HMS Mortar was his first command appointment.
Mr Hunt's two Lieutenants were appointed by the Admiralty and the senior Warrant Officers by the Navy Board, including the vessel's Standing Officers; those men who would remain in HMS Mortar whether or not she was in commission. In a Bomb Vessel, the Standing Officers would be:
The Boatswain - a man with many years sea service under his belt who had come up from amongst the ranks of seamen. Responsible for the repair, operation and maintenance of the vessels boats, masts and rigging, he was accountable to the First Lieutenant and was assisted when the vessel was in commission by a single Boatswains Mate.
The Gunner - another man who had risen from amongst the ranks of seamen. He was responsible for the maintenance, repair and operation of the vessel's main guns. He was responsible also for the training of both the gun crews and of any Midshipmen in Ordinary in the arts of gunnery. He was assisted when the vessel was in commission by a single Gunner's Mate. He reported to the First Lieutenant. The operation and maintenance of the mortars was a very specialised task and would be carried out by officers and soldiers of the Royal Artillery seconded to the vessel by the Army.
The Purser - Responsible for the purchase and distribution of the vessel's victuals and stores. When the vessel was not in commission, he was allowed to live ashore within a reasonable distance of the Dockyard. He answered directly to the Commander.
The Carpenter - He was a qualified shipwright who was responsible for the repair and maintenance of the vessel's hull, frames and decks. When the vessel was in commission, he was assisted by a single Carpenter's Mate.
The other Warrant Officers, appointed by the Commander on the recommendation of the First Lieutenant having applied for the position and presenting their credentials were:
The Armourer - Answerable to the Gunner, he was a qualified blacksmith who was responsible for the repair and maintenance of the vessel's stock of small-arms and bladed weapons. He could also manufacture new bladed weapons if required and also fabricate any iron parts of the vessel if necessary.
The Sailmaker - Answerable to the Boatswain, he was responsible for maintenance and repairs of the vessel's sails and the storage of spare sailsand the vessel's stock of flags.
The Caulker - Answerable to the Carpenter, he was responsible for ensuring that the hull remained watertight.
The Surgeon - Answerable to the Commander, he was responsible for the healthcare of the whole crew. Although not a doctor, the Surgeon had had to complete a seven-year apprenticeship overseen by the Royal College of Surgeons and the Royal College of Physicians. In a Bomb-Vessel, the Surgeon was assisted by a single Assistant Surgeon, himself a part-qualified Surgeon.
The Sailing Master - Answerable to the Commander, the Sailing Master was a fully qualified Ship's Master in his own right, able to work in the merchant service as such when not employed by the Royal Navy. He was responsible for the day to day sailing and navigation of the vessel and was assisted in this by a single Masters Mate, himself a qualified Ship's Mate.
The Ropemaker - Answerable to the Boatswain, he was responsible for the storage of the vessel's stock of cordage and the manufacture of new cordage should it be required.
The Clerk - Asnwerable to the Purser, he was responsible for keeping all the vessel's records and sending them to the Admiralty as required.
The Master at Arms - The vessel's policeman, responsible for the day to day enforcement of discipline aboard and answerable to the First Lieutenant. He was assisted by a single Corporal.
A Bomb Vessel like HMS Mortar would have two Midshipmen. Appointed by the local Commander in Chief, they were commanders in training and their job was assist the Lieutenants in their day to day duties. In addition to the Midshipmen, HMS Mortar may have had up to four Midshipmen in Ordinary amongst her company. These young men, usually in their early teens were officers in training and were usually related to the Commander or were the sons of people the Commander either owed a favour to or was doing a favour for. The commander of a vessel like HMS Mortar with a crew of 60 men would be entitled to have up to four servants. Unless he was extraordinarily extravagant, he wouldn't require this number, so the spare positions were taken up with the Midshipmen in Ordinary. They wore the uniform and performed the duties of a Midshipman but were on the vessel's books as Commander's Servants and were rated at and received the pay of an Able Seaman.
HMS Mortar was declared complete on the 28th June 1759. On completion, HMS Mortar was a vessel of 313 tons. She was 92ft long at the main deck and 74ft 8in along the keel. She was 28ft 1in wide across her beams. She was armed with 8 x 6pdr long guns on her main deck with 14 x half-pounder anti-personnel swivel guns attached to her bulwarks and in her fighting tops. She carried 1 x 13in mortar and 1 x 10in mortar in addition to her guns. The vessel had cost £3,757.14s.6d to build and £2,015.0s.1d to fit out.
Infernal Class PlansInternal Deck Plans:
Sheer Plan and Lines:
A model of the centre section of a Bomb Vessel c. 1760. In view of the date, this is very likely to be an Infernal Class vessel. Notice the scale of the supports for the mortar bed. Notice also the swivel guns:
A model of the Bomb Vessel HMS Grenado. Launched in 1742, HMS Grenado was somewhat earlier than HMS Mortar, but apart from being slightly smaller, shared the same layout and general appearance. The model shows the mortar beds and her unusual and ungainly-looking ketch rig:
In early 1759, the British became aware of French plans for an invasion of Britain. This was to involve the transport of 100,000 French troops in a huge fleet of barges and flat-bottomed boats across the English Channel. The invasion fleet was to be built in Le Havre, Brest, Morlaix, Lorient and Nantes. Initially, the plans were to involve a Jacobite uprising in Scotland under Charles Stewart, the so-called Bonnie Prince Charlie, but this part of the plan was cancelled after the Young Pretender turned up to a meeting with the French military High Command late and drunk. Nevertheless, plans for the invasion continued to evolve such that by the summer of 1759, it had been decided that the invasion would be launched from Le Havre alone and that the hundreds of invasion craft should gather there to await favourable winds, to carry them to the Portsmouth area where they were to land. The British laid their own plans to counter the invasion threat. Admiral Sir Edward Hawke, commanding the Royal Navy's Channel Fleet was to mount a close blockade of the main French naval base at Brest to prevent them from being able to escort the invasion force across the English Channel, while troops were stationed on the Isle of Wight and shore batteries thrown up near likely landing sites. In the early summer, intelligence reached London that the French intended to try to send the fleet unescorted.
In late June 1759, Rear-Admiral Sir George Brydges Rodney was ordered to take a squadron of five ships of the line, five frigates, a sloop of war and six Bomb Vessels to Le Havre and destroy the invasion fleet. On 2nd July 1759, Rodney and his force left the fleet anchorage off St. Helens, Isle of Wight, bound for Le Havre. His force comprised HMS Achilles (60 guns, flagship), HMS Chatham, HMS Isis, HMS Norwich and HMS Deptford (all of 50 guns), the frigates HMS Brilliant and HMS Juno (both 12pdr-armed ships of 36 guns), HMS Vestal (12pdr-armed, 32 guns), HMS Boreas and HMS Unicorn (both 9pdr-armed ships of 28 guns), the ship-rigged Sloop of War HMS Wolf of 16 guns and the bomb vessels HMS Furnace, HMS Firedrake, HMS Blast, HMS Basilisk, HMS Mortar and HMS Carcass.
Rodney's force arrived off Le Havre the following day and Rodney issued his orders. He was acutely aware of the importance to the whole mission of the Bomb Vessels, so wrote the following orders for his Flag Captain, Captain the Honourable Samuel Barrington to pass on to the other ships:
"
You are hereby required and directed to keep His Majesty's Ship under your command in constant readiness for action and your boats manned and armed with five grapnels in them, who, when any of the bombs are attacked or have an appearance of it, are immediately to go to their assistance
Given under my hand on board the Achilles at sea 3rd July 1759"
Commander Hunt had his vessel anchored such that they could traverse the mortars by adjusting the anchor cables to shift their targets. At noon on 4th July 1759, the bombardment of Le Havre began. Over the course of the next 52 hours, the Bomb Vessels fired some 3,000 shells into the magazines, shore batteries, invasion vessels and into the town of Le Havre itself and did immense damage. Despite the efforts of hundreds of men to fight the fires, Le Havre continued to burn for six hours after the British finally ceased firing. French plans to launch their invasion of Britain from Le Havre were in ruins. Although the Bomb Vessels and ships of the line returned home, Rodney stayed behind with the frigates and over the course of the next few months took many prizes.
The Bombardment of Le Havre, 4th to 6th July 1759. Painting by Joseph-Abel Couture.
Meanwhile, the French pressed on with their plans. An alternative plan was hatched to launch the invasion with the remaining invasion craft from Brest, to be escorted across the English Channel by the combined French Brest and Toulon Fleets and land at Maldon in Essex and in Scotland to support a planned Jacobite uprising, dividing the defending British. The Toulon Fleet was caught and scattered by the British Mediterranean Fleet under Admiral Sir Edward Boscawen at the Battle of Lagos in August of 1759 and the Brest Fleet was smashed by Admiral Sir Edward Hawke at the Battle of Quiberon Bay the following November. After those two crippling defeats, the French called off the planned invasion.
With the threat of invasion over, the priority for the Channel Fleet became that of containing the French Atlantic fleet in it's bases. In order to do that, the Royal Navy needed fewer Bomb Vessels and more Sloops of War. In April of 1760, HMS Mortar entered the Royal Dockyard at Portsmouth to be converted into a Sloop of War. The work entailed the removal of the mortars, their beds and the reinforcements to the vessel's frames. She was re-rigged with a ship rig, with three masts and was fitted with an additional six six-pounder long guns on her main deck. The vessel was re-established as a 14-gun Sloop of War. The additional guns and the additional mast meant that HMS Mortar's complement rose from 60 men to 110.
On the 21st November 1760, Mr Hunt was Posted and appointed Captain in the Frigate HMS Unicorn. He was killed in action when his ship engaged and captured the French 12pdr-armed, 32-gun Frigate La Vestale off Penmarsk on the 8th January 1761.
Mr Hunt's replacement in HMS Mortar was Mr John Symonds. Mr Symonds was born in 1732 and entered the Royal Navy at the age of 15 in 1747. He had passed his Examination for Lieutenant on the 14th November 1753 and HMS Mortar was his first command appointment. He commanded the ship until the end of the war, ended by the Treaty of Paris signed on the 10th Februry 1763. On the 12th May 1763, HMS Mortar was paid off into the Portsmouth Ordinary. Mr Symonds was Posted on the 28th January 1771 and died a Vice-Admiral on the 16th December 1799.
HMS Mortar remained in the Portsmouth Ordinary under the care of a skeleton crew comprised of her Standing Officers and their servants. A Bomb Vessel would not have had any seamen attached to her skeleton crew, instead men would be assigned to assist by the Master Attendant at the Dockyard.
HMS Mortar remained in the Portsmouth Ordinary until she was recommissioned under Mr James Howell Jones on the 26th May 1768 and fitted for sea. Mr Jones had first passed his Examination for Lieutenant on the 27th November 1760 and his previous appointment had been as Lieutenant in Command in the Armed Cutter HMS Wells of six guns. Mr Jones remained in command until the 10th December 1770 when he paid the ship off again at Portsmouth.
HMS Mortar remained in the Portsmouth Ordinary until she was sold out of the service for £400 on the 2nd September 1774.