INVOCAV1T IODINE. 



and their control was supported by means against 

 which the church was wholly inadequate to contend. 

 The estates and honours which composed the eccle- 

 siastical temporalities, were considered to partake of 

 the nature of fiefs, and therefore to require similar 

 investiture from the lord. Cliarlemagne is said to 

 have introduced this practice, and to have invested 

 the newly consecrated bishop by placing a ring and 

 crosier in his hands. Gratian, ndeed, (Distinct. G3, 

 cap. Adrtanus), directly affirms that pope Adrian 

 positively conceded to the emperor the power of 

 electing, even to the papacy, in 774 ; but neither 

 Eginhard nor any other contemporary writer men- 

 tions this fact. 



The custom, however, existed, nor does it appear 

 to have been objected to or opposed during the lapse 

 of two centuries from his reign. The disorderly state 

 of Italy, which succeeded the death of Charlemagne, 

 frequently interrupted the exercise of this right by 

 the Carlovingians ; but even so late as 1047, when 

 the empire had passed to another line, Henry HI. 

 received an explicit admission of his prerogative, and 

 repeatedly used it. The investiture in the lesser 

 sees followed as a matter of course. Alexander II. 

 issued a decree against lay investiture in general, 

 which was revived by Gregory VII. (Hildebrand), 

 who, having succeeded in annulling the prerogative 

 of the emperors to nominate or confirm popes, sought 

 to disjoin entirely the ecclesiastical from the civil 

 rule. He complained loudly of the humiliation to 

 which the church was subjected by dependence upon 

 the patronage of laymen, and condemned with far 

 more reason the mercenary and simoniacal exactions, 

 which ecclesiastics suffered from temporal princes as 

 the price of the benefices which they conferred. In 

 the council of the Lateran in 1080, he declared that 

 no bishop or abbot, submitting to lay investiture, 

 should be considered a prelate. The convulsions 

 which followed engendered the Guelf and Ghibeline 

 factions (see Guelf), and deluged Italy with blood for 

 a long series of years ; for the struggle commenced 

 by Gregory with Henry IV. was zealously continued 

 by his successors, among whom Urban II. and 

 Paschal II. especially distinguished themselves. It 

 was not, however, until the papacy of Calixtus II., 

 in 1122, that the question was terminated, as it 

 appears, materially to the advantage of the holy see. 

 By a concordat then arranged at Worms, Henry V. 

 resigned for ever all pretence to invest bishops by 

 the ring and crosier, and recognised the freedom of 

 elections : the new bishop, however, was to receive 

 his temporalities by the sceptre. In France, even 

 under the papacy of Hildebrand, the right of investi- 

 ture does not appear to have been made a subject of 

 open quarrel. In spite of the protests of the holy 

 see, the kings exercised the power, but at length 

 relinquished the presentation of the ring and crosier, 

 and contented themselves with conferring investiture 

 by a written instrument, or orally, upon which they 

 were left in peaceable possession of the power. But 

 in England, Paschal II. was engaged in a contest 

 little less fierce than that which he maintained with 

 the emperor. Anselm, the primate, refused to do 

 homage to Henry I. for his see. The king seems to 

 have asserted an unqualified right of investiture, 

 which the pope, who was appealed to, as unquali- 

 fiedly denied. After a protracted struggle, and con- 

 tinued threats of excommunication, the controversy 

 ended in England, as it did afterwards in Germany, 

 by compromise. Paschal offered to concede the 

 objections against homage, provided Henry would 

 forego the ceremony of investiture. To this he 

 agreed. 



INVOCAVIT ; the first Sunday in Lent, so called 

 because the primitive church began their worship, on 



that day, with the words of the 9 1st Psalm, 15th 

 verse, Invocavit me ct exaudiam eum. It is also 

 called Quadragesima, or the fortieth day, because it 

 is forty days before Good Friday, the day when Lent 

 ends. 



INVOICE; an account, in writing, of the parti- 

 culars of merchandise, with their value, customs, 

 charges, &c., transmitted by one merchant to ano- 

 ther. 



INVOLUTION, in mathematics; the raising of a 

 quantity from its root to any power assigned. Thus 

 2x2x2 = 8. Here 8, the third power of 2, is 

 found by involution. By continuing the process, 

 we can obtain any power of 2, and so with other 

 numbers. 



IO ; daughter of Inachus (according to some, of 

 Argus Panoptes) and Peitho ; according to others, of 

 lasus and Leucane. Jupiter fell in love with her. 

 At first, she would not listen to his wishes ; but, 

 being enveloped by him with a thick cloud, she 

 yielded herself to his embraces. Juno, notwith- 

 standing, perceived the infidelity of her husband, and 

 resolved to be revenged on both. Jupiter, to pro- 

 tect lo from the jealousy of Juno, changed her into 

 a beautiful white heifer. Juno was not deceived, 

 and begged the heifer of her husband. Apprehend- 

 ing no evil, he granted her request ; but she imme- 

 diately placed it under the custody of the hundred- 

 eyed Argus. Jupiter now regretted that he had 

 complied with her request, but it was too late ; he 

 therefore sent Mercury to kill Argus, and set lo 

 at liberty. This commission Mercury successfully 

 executed, having lulled the watchful Argus to sleep 

 by playing on the flute ; but at the moment when lo 

 thought herself again at liberty, the jealous Juno 

 afflicted her with madness, and persecuted her with- 

 out a moment's rest, through the world. She sprang 

 into the Ionian sea, reached Illyria, passed the 

 Haemus, went through Thrace, swam over the 

 Thracian Bosphorus to Asia, passed through Scythia, 

 over Caucasus, and came at length to Egypt. She 

 found Prometheus in the Caucasian mountains, who 

 comforted her, and showed her the way she must 

 take. This way is described at length in the " Pro- 

 metheus" of yEschylus. Her sufferings ended in 

 Egypt. Here she regained her original form, and 

 bore Epaphus, the son of Jupiter. At the instiga- 

 tion of Juno, the Curetes concealed the child, and 

 were, in consequence, struck with lightning by Jupi- 

 ter. After a long search, lo found her son in Syria, 

 and returned with him to Egypt, where she married 

 the king, Telegonus. She was deified, and, accord- 

 ing to some authorities, was the goddess whom the 

 Egyptians worshipped under the name of Isis. 



IODINE (from ia^s, vioalaceus, in allusion to the 

 beautiful violet colour of its vapour) is the name of an 

 undecompounded principle or element in chemistry. 

 It had escaped the observation of chemists until 

 1812, when a manufacturer of saltpetre, at Paris, 

 detected it in the ashes of sea-weeds, in the following 

 manner. In evaporating the ley from these ashes, to 

 procure the carbonate of soda which they contain, he 

 noticed that the metallic vessels, with which he ope- 

 rated, were powerfully corroded, and that the cor- 

 rosion was increased as the liquor became more 

 concentrated. Having at hand, one day, a bottle of 

 sulphuric acid, he added some of it to a portion of 

 the mother-water, and was surprised to see a rich 

 violet vapour disengaged ; this vapour was the 

 iodine. He at once communicated the observation 

 to M. Clement Desormes, who set about collecting 

 some of the vapour, and, after examining its leading 

 properties, announced it to the royal institute of 

 France as a new body. Its real nature was soon 

 after unfolded through the accurate researches of 



