In Fig. 4 an attempt has been made to show the gradual development of the ordinary hand hammer from the earliest known types. The illustrations show broadly the various stages it has passed through and the many methods adopted for attaching the head to the shaft or handle. As in all human inventions progress has been made in a series of steps.

The hammer, a tool of percussion, is the most widely used of all tools. The prototype of the hammer is of course found in the clinched fist, a tool or a weapon according to circumstances, and one that man soon learned to use. When he found that this was not hard or powerful enough he would naturally look around for something better, and this he found in rounded pebbles. These were used by primitive man for many purposes, and it is only when the stone was chipped or marked by blows caused through working on a harder material that it can be recognized as having been used as a hammer.

Fig. 4, No. 1, shows a piece of flint that has been used as a hammer. It was held in the hand and is known as a hammer stone. Some hammer stones were oval in form, and others had pits or depressions chipped out of both sides for the thumb and finger to fit into so that a better grasp could be obtained. Fig. 4, No. 2, shows a hammer head of deer horn with a hole for the handle. This is in the British Museum and was found in a British barrow in association with a burnt body at Lambourn Downs, Berkshire. In the Guildhall Museum there are some hammers complete with handles made from the antlers of the red deer. Fig. 4, No. 3, is an oval stone hammer grooved for the purpose of lashing it to a handle. Similar forms were used as net sinkers, as is indicated by names and description in the Pitt-Rivers Collection at Oxford. Fig. 4, No. 4, is from the Horniman Museum, and was held in the hand. This comes from Vancouver in North America. A similar object was used in Tahiti for pounding bread fruit and called a pounder. Fig. 4, No. 5, is a quartzite hammer made from a pebble, and the hole has been made by pecking or drilling a pit on either side until the two depressions met. For drilling the holes the drill was simply a stick twirled between the palms of the hand and fed with sand and water (see Fig. 6). Some of the European specimens were perforated by means of a piece of cane twirled between the hands and fed with sand and water as illustrated in Fig. 6, No. 4. Fig. 4, No. 6, is a decorated hammer head, and was probably not used for serious work. There is in the British Museum a broken portion of a stone hammer decorated with a number of lines arranged to form an all-over pattern, and perforated for the reception of a shaft; this was found in a Mycenaean tomb that dates back to about 1350 b.c. Fig. 4, No. 7, is a stone hammer that was found in the Thames. Fig. 4, Nos. 8 and 9, illustrate hammers of cast bronze hollow at the top end for the insertion of a shaft. That shown in No. 8 was found at Thorndon in Suffolk, and No. 9 comes from Ireland. The round heads shown in No. 9 are simply decorative. Fig. 4, No. 10, shows a limestone mould for casting hammer heads. At the bottom of the mould a depression will be noticed. This was for the reception of a core or circular piece of clay or soft stone, so that when the metal was poured into the mould it would flow round this core, and when the metal had solidified and was removed from the mould and the core taken out a hole would be left ready for the shaft. Fig. 4, No. 11, is a cast bronze hammer head about 7 in. long and 3 1/2 in. in diameter and has been much used. Fig. 4, No. 12, is an iron claw hammer practically the same shape as the modern tool. Fig. 4, No. 13, is also of iron, and it has a thin pene and a rectangular face. Fig. 4, No. 14, is a German claw hammer with a square face and the claws rounded on the top and decorated on the sides with engraved lines and dots. Fig. 4, No. 15, is a modern example of an engineer's or fitter's hammer made of steel with hardened face and pene. In the Guildhall Museum there are two hammer heads of interest, one is an iron war hammer, or as it is called, Martel de fer, of the fifteenth century. It is similar in shape to our present-day double square face planishing hammer, with the exception that the faces have nine projecting spikes about half an inch long, thus making it more of a club. The other is a Roman claw hammer of a peculiar shape and made of iron. This was found at Austin Friars.

How the hammer stone became a hammer head is not known, but nearly all the stone-headed hammers from various countries show very simple methods of hafting, and the smith of to-day holds various tools in the manner that was usual in the early centuries. The illustrations forming Fig. 5 show various methods of hafting, so that a larger amount of power can be obtained without hurting the arm or wrist. In Australia the Aborigines fixed the stone head of their hammer to a handle made from the small branch of a tree, with a kind of gum or cement (see Fig. 5, No. 1). Fig. 5, No. 2, shows how the head, which has a groove round the centre, was fastened by means of moistened strips of hide which contracted in the drying, so binding the stone head firmly to the handle. In Fig. 5, No. 3, the head is wrapped round twice with a flexible branch and tied with split rattan. Fig. 5, No. 4, is a stone hammer head with one flat side fitted to a piece of a tree from which a branch has grown out at right angles and the stone head is tied on with sennit cord. The head of Fig. 5, No. 5, is attached to the handle by means of a leather thong. Sometimes the handle and binding is in one piece, as when it is made of substance like whalebone or horn and tied round the head and then round the shaft while in a pliable condition. When it dries, it hardens and is practically irremovable. Fig. 5, No. 6, shows a haft of flexible wood cut away and then bent round the head and pegged down. Fig. 5, No. 7, is a right-angled branch and the end is fitted tightly into the hole left in the bronze hammer head. It is tied on with sinews or strips of hide. These bindings were very often done in quite a decorative manner. In Fig. 5, No. 8, a piece of wood is wedged into the hammer head and this is fitted to a shaped shaft that has a rectangular hole in it. The piece of wood with the hammer head fixed to it was put through the hole and kept in position by a taper wedge. Fig. 5, No. 9, has a hole right through the hammer head which is of bronze, and the end of the shaft is split and a simple taper wedge of wood driven in. In Fig. 5, No. 10, a withy, or willow branch, is wound twice round the cold sett and an iron coupling or ring slipped on. Fig. 5, No. 11, shows a modern method of holding a flatter. A piece of 5/16 in. round iron is made red hot and bent twice round the flatter so that when it cools it holds the tool firmly. Two holes are then drilled close together in a hammer shaft, the ends of the rods are bent at right angles and put through the holes in the shaft, bent over and clinched. A collar from 3/4 x 3/16 in. iron is then made and shrunk on. Fig. 5, No. 12, is a modern method of fixing an engineer's hammer to the shaft. The shaft is fitted to the eye and then cut down with a saw parallel with the head. A wedge of iron is made with a number of burrs thrown up on the faces and edges with a diamond-pointed chisel. When the wedge is driven in the burrs catch in the wood and the head does not readily work loose. This kind of hammer is made heavier at the face than at the pene end so that it will naturally assume a position in the hand with the face downward, so relieving the user from the necessity of specially forcing it into that position. In using a hammer it is essential to study the difference between a sharp blow with a light hammer and a slow blow with a heavy one, the former penetrates the farthest and gives least lateral pressure, while the latter penetrates less and spreads more.

Fig. 5. The evolution of the hammer.

Fig. 5.-The evolution of the hammer.

Of modern hammers there is a great variety, and a volume could be written on this subject alone, for each particular trade has its own set, and a set comprises any number. There are also the mechanically operated hammers, such as the trip or tilt hammer, the steam hammer, and the pneumatic hammer. When one considers all the hammers, from the tiny ones used by the jeweller to the mighty steam hammer with its hundred-ton blow, we are bound to marvel at man's ingenuity.