HELMET SHELL 



favoured a high crest of horsehair, 

 but the Romans, while adopting the 

 general lines of the Greek head- 

 piece, were content with a much 

 smaller crest, frequently a mere but- 

 ton or knob. Assyrian, Egyptian, 

 and Etruscan helmets were planned 

 on the same general principles 

 though differing in design, and, like 

 the Greek, were frequently orna- 

 mented with rich decoration. 



After the fall of the Roman 

 Empire, the helmets of Central 

 Europe were cruder in manufacture, 

 frequently mere caps of toughened 

 leather, or of plates of bronze or 

 iron 'riveted to a ring. The pointed 

 helmet of the Normans was of 

 this nature, but it was generally 

 provided with a strong nasal or 

 nose guard, of large proportions, 

 attached to the base of the ring. 

 From this time onwards the design 

 of the helmet progressed ; some- 

 times it was a small, close cap of 

 steel, and sometimes a broad- 

 brimmed defence. In the 14th 

 century the popular type was 

 known as the bascinet, a light, 

 pointed helmet, sometimes with 

 a visor pivoted to the sides, and 

 generally attached to the camil or 

 coif of mail by staples and laces. 

 In the 15th century we find the 

 salade commonly in use. This was 

 a helmet very similar in design to 

 the modern sou' -wester, with fixed 

 or pivoted visor, and with an 

 adjustable beaver, or chin piece. 

 From this latter was evolved 

 the armet or close helmet, which 

 completely encased the head, and 

 had two movable pieces to cover 

 the eyes and mouth respectively. 

 From this again was evolved a 

 simpler form, called the burgonet. 



At the end of the century, when 

 full armour was being discarded, 

 the morion and cabasset, light, 

 open helmets, came into favour. 

 In the 18th century, a helmet 

 based somewhat on the Greek 

 form was adopted for heavy 

 cavalry by most European armies, 

 and this in turn gave place to the 

 graceless helmets of the dragoons 

 and household cavalry worn only 

 for ceremonial parade. The modern 

 shrapnel helmet is based upon the 

 chapel de fer of the 15th century, 

 the French casque on a compromise 

 between the morion and cabasset, 

 while the German helmet is almost 

 a copy of a variety of the salade. 

 The great helm of the 13th century 

 was of barrel form, heavy and cum- 

 bersome, with a flat top which 

 was entirely unpractical as pro- 

 viding no glancing surface to the 

 opposing weapon. At the end of 

 the century we find the more prac- 

 tical sugar loaf helm. 



In the 14th century She helm has 

 a rounded top with a projecting 



3928 



face-plate and a narrow ocularium 

 or vision slit. In jousting helms this 

 slit was so placed that the wearer 

 could only see out of it when he was 

 bent forward with lance in rest 

 ready for his course. The helms of 

 the 15th and 16th centuries were 

 bolted to the cuirass back and 

 front, and presented a smooth sur- 

 face to the attacking weapon. 



In heraldry the first type of helm 

 employed was cylindrical, with 

 sqxiare or flat top ; then came the 

 round. In early 

 art the helmet 

 was always 

 represented as 

 disproportion - 

 ately large as 

 compared 

 with the 

 shield, and was 

 Helmet as an heraldic placed i n- 

 charge differently full 



face or in profile. Gradually rules 

 were introduced, the open visored 

 helmet being reserved for princes 

 and nobles and the closed for 

 lesser folk. Modern practice enj oins 

 that the sovereign and princes of 

 the blood should have a helm 

 of gold, with seven-barred visor 

 (grilles) placed full face, or 

 affrontee. 



A peer has a silver helmet, with 

 five golden bars, in profile to dex- 

 ter ; baronets and knights a steel 

 helmet, represented in painting by 

 light blue or grey, full faced, with 

 open visor ; esquires and gentlemen 

 of coat armour, a steel helmet in 

 profile, with closed visor. No 

 woman, except a sovereign, is en- 

 titled to the helmet. See Armour ; 

 Casque; Celt; Crest. 



Helmet Shell. Popular name 

 for the shells of the genus Cassis, 

 which includes numerous marine 

 gasteropodous molluscs found in 

 ~i the tropical 

 seas. The 

 shell" are mas- 

 sive and ven- 

 tricose, with 

 a narrow aper- 

 ture. There 

 are about 50 

 species, many 

 of which at- 

 tain a large 

 size and are 

 handsomely coloured. From these 

 shells the best shell cameos are cut. 

 Helmholtz, HERMAN LTJDWIG 

 FERDINAND VON (1821-94). Ger- 

 man physicist. Born at Potsdam, 

 A-Jg. 31, 1821, Helrnholtz was a de- 

 scendant of the Quaker William 

 Penn. He made a study of medi- 

 cine, and from 1843-47 served as a 

 surgeon in the Prussian army. 

 He held the chair of physiology 

 at Konigsberg, Bonn, and Heidel- 

 berg universities, 1849-71, and in 



Helmet Shell. Speci- 

 men of Cassis Mada- 

 gascariensis 



H. von Helmholtz, 

 German physicist 



HELMSTEDT 



the latter year became professor of 

 physics at the university of Ber- 

 lin. His most important post 

 was that o! 

 director of the 

 Physico-techni 

 cal Institution 

 of Chariot-ten- 

 berg, to which 

 he was appoin- 

 ted in 1887. 



Hel mholtz 

 was responsible 

 for many ad- 

 vances in the 

 study of the eye and the nervous 

 system. The invention of the 

 ophthalmoscope is due to him, one 

 of the most remarkable of all instru- 

 ments used by the oculist. In 

 1856-66 was published his work 

 Physiological Optics, one of the 

 greatest advances in the theory 

 of vision, etc., of the 19th century. 

 His work on hearing, entitled 

 Sensations of Tone, published in 

 1863, holds a corresponding position 

 in acoustics. 



The great physicist was one of 

 the founders with Lord Kelvin of 

 the theory of the conservation of 

 energy ; to him is due the theory 

 of colour depending on the three 

 fundamental sensations .of red, 

 green, and blue or violet ; the study 

 of the electromagnetic theory of 

 light ; of vortex motion ; and the 

 problems of electro-dynamics. He 

 died at Charlottenberg, Sept. 8, 

 1894. Consult Life, L. Kdnigs- 

 berger, Eng. trans. F. A. Welbv, 

 1906; H. L. F. von Helmholtz, 

 J. McKendrick, 1899. 



Helmond. Town of Holland. It 

 stands on the Aa, in the province of 

 N. Brabant, 28 m. from Hertcgen- 

 bosch. The chief building is the 

 castle, finished about 1400. There 

 is also a fine church dedicated to 

 S. Lambert, and a town hall. The 

 town is served by railway, canal, 

 and tramway, and its industries are 

 chiefly connected with the making 

 of cotton and silk goods. There are 

 also engineering works, and those 

 for making soap, tobacco, and beer. 

 Pop. 14,800. 



Helmont, JEAN BAPTISTE VAN 

 (1577-1644). Belgian alchemist. 

 Born at Brussels and educated at 

 Louvain, his outstanding discovery 

 was carbonic acid gas, which lie 

 named yas sylvestre. This was re- 

 discovered by Black in the 18th 

 century, and called fixed air. He 

 died at Vilvorde, Dec. 30, 1<>44 

 See Alchemy. 



Helmstedt. Town of Germany. 

 in Brunswick. It lies 29 m. E.N.E. 

 of Magdeburg. It was once famous 

 for its university, which was 

 founded in 1576 and suppressed in 

 1809. The old building of the uni- 

 versity is in the Renaissance style. 



