This militia act was due to an invasion scare in 1756 because Great Britain then had no allies on the continent. The old strategy of maintaining a small army of 17,000 men and relying on volunteers had really depended on England's allies to tie down France's land forces. The militia act of 1757 was designed to reassure squires they would not be used as adjuncts to the army. Only those with much property could be officers. Enlistees could still carry on their trades and jobs. Costs were to be from general taxation rather than by locality. But it was almost impossible to get officers and there were many riots when parish authorities tried to draw up lists of those liable to serve. In 1759 the navy prevented French invasion.

Able-bodied men without a calling, employment, or visible means of maintenance or livelihood could be searched for and conscripted into the army. Volunteers who enlisted were paid 40s. and were not taken out of her majesty's service by any process other than for some criminal matter. King George II was the last king to lead his troops into battle. Later, parishes were given 20s. for every soldier they summoned. Also, persons who had a vote for member of Parliament were exempted.

Whipping was the usual punishment for offenses. A soldier who deserted or joined in any mutiny or sedition in the royal army within the realm was to suffer death or any other punishment determined by court martial. In 1760, a soldier (later, or a marine) who slept at his post, left his post before being relieved, communicated with any rebel or enemy, struck or disobeyed any superior officer could suffer death, including those soldiers in America.

During war, chief officers of towns quartered and billeted royal army officers and soldiers in inns, livery stables, alehouses, and victualing houses for 4d. a day, but not in any private house without consent of the owner. From 1714 to 1739, the army regiments were split up and scattered among the ale-houses of small towns for maintenance; this was to disperse the soldiers. It was easier to count them, thereby keeping a check on their number, which might be exaggerated if they were in large groups in barracks. The towns protested having to maintain soldiers and town magistrates imposed severe penalties for small offenses by soldiers. Their drunkenness and violence were not tolerated as they were for ordinary people. Their officers not being with them, the soldiers retaliated with troublesomeness. As of 1763 English troops could be quartered in unoccupied houses or barns and supplied with necessities such as bedding, firewood, candles, vinegar, salt, cooking utensils, and beer or cider. The Royal Hospital gave pensions to maimed and worn out soldiers treated there.

Sailors had more status than soldiers because they had regular work as seamen in times of peace and they did not remind the people of the idea of a standing army, which they had hated especially since Cromwell.

Justices of the Peace, mayors, and other officers could bind boys as apprentices to sea service if they were at least ten and their parents were chargeable to the parish or begged for alms. This indenture to the masters or owners of ships lasted until the boy reached 21. The boy's parish paid 50s. for clothing and bedding for such sea service. No such apprentice could be impressed into the navy until at least 18 years of age. Master and owners of ships that carried 30-50 tuns had to take one such apprentice and one more boy for the next 50 tuns, and one more boy for every 100 tuns over 100 tuns, or else forfeit 10 pounds to the boy's parish. Boys voluntarily binding themselves to such sea service were exempt from impressment for the next three years. This was to increase the number of able and experience mariners and seamen for the navy and for the trade and commerce of the nation.

No masters or commanders of merchant ships were to proceed on a voyage beyond the seas without first agreeing in writing on wages with the seamen, except for apprentices. Such agreement had to be signed by the seamen. Offenders were to forfeit 5 pounds per seaman, which sum went to the use of Greenwich Hospital. Any seaman leaving the ship before being discharged in writing was to forfeit one month's pay because too many left the ship before it was unladen.

There were some ships of 2000 tons. The steering wheel had been introduced because a sudden heavy sea could wrest a tiller from the hands of a helmsman. Triangular head-sails with jib boom and stay-sails on stays between masts were in use so that ships could sail closer into the wind. The length of ships was still determined by the same length of trees that could be grown. Sailing ships were still vulnerable to a lee shore. Latitude was easy to determine using the reflecting octant invented by John Hadley in 1731, and a sextant invented in 1757, with mirrors and a small telescope to measure the angle between a celestial body such as the sun or north star and the horizon. But longitude could not be determined with any degree of accuracy. One method relied on accurate predictions of the future position of the moon as observed from a fixed reference point, such as Greenwich. By precisely observing the local time of the moon's occultation of a known star at a particular place, and looking up in a table the predicted time of the event at Greenwich, one could approximate the time difference of the place from Greenwich. There were so many shipwrecks on this account that the government offered a reward to anyone who found a way to measure longitude accurately. In 1763 carpenter and clockmaker John Harrison made the chronometer to do this with an accuracy of 2 1/2 seconds per month, and received 5,000 pounds. He was promised 10,000 pounds to explain the principle of his timekeeper and build three more. The chronometer kept time with extreme accuracy and was mounted to remove the effect of the ship's motion. To find a ship's position, a navigator noted the time and measured the positions of certain stars. He compared these positions with tables that showed the stars' positions at Greenwich mean time, and then calculated the ship's position.

Officer positions were no longer bought, but were subject to examination for a minimum of knowledge, especially in navigation. In 1729 the Naval Academy was established. Boys entered at age 13 to 16 and spent two or three years there.

Only about 15% of the crew of navy ships were volunteers. Many were gaolbirds, having chosen the Navy over more gaol time for debt. Press gangs seized men in the port towns and from ships coming into harbor. From 10% to 20% of the crew were foreigners, many of these pressed men. About 1756, the Marine Society was founded for training and placing poor boys in work in naval and merchant ships. This not only supplied men and boys for the Navy, but saved boys from a life of vagrancy and crime. These boys usually became reliable and obedient sailors.