38 THE MICROSCOPE. 



various ones having them in use. One Scarrdro Dipopozzo,' an 

 ItaUan, wrote in 1293 that it was impossible for him to read without 

 his " lunettes," the name then used for glasses or specs. Alex. 

 Spina, native of Pisa, who died in 1315, made specs for himself and 

 afterwards for others.' Inscribed on the tomb of Salvinus Arm- 

 atus, a nobleman of Florence, who died in 1317, is an inscription 

 which ascribes to him the honor of inventing spectacles. 



Concave glasses no doubt followed very closely the first use of 

 convex lenses, for Maurolycus, who died in 1575, explains the use 

 of both kinds of glasses and does not mention either of them as a 

 recent invention. 



BONE IN THE EYE. 



BY H. GIFFORD. 



THE following somewhat peculiar case of ossification in the eye 

 occurred in a young man, twenty-four years of age, oper- 

 ated on by Prof. Frothingham, at the Eye Clinic of the Uni- 

 versity of Michigan, Dec. 21, 1881. 



Twelve years before, the eye had been struck by a piece 

 of gun-cap, though the exact seat of the blow could not be 

 ascertained. The eye became blind within three days and 

 from that time had no perception of light. As it was so pain- 

 ful at times it was enucleated to guard against sympathetic 

 trouble. 



Immediately after its removal the eye was opened by a 

 longitudinal section, as the gun-cap was supposed to be within, 

 but this proved not to be the case. The eye was then hard- 

 ened in alcohol and re-examined with the following results : 

 Bulb, somewhat irregularly atrophied, 14 mm. in diameter, scler- 

 otic much thickened, 2 mm. thick in posterior hemisphere ; re- 

 tina closely adherent to the choroid ; vitreous liquefied. In 

 the place of the lens was a nucleus of solid bone, about 

 5x2 mm, surrounded by a thin layer of osteoid tissue, the 

 remainder of the lens-form being filled out with a finely fibril- 

 lar structure, containing numerous round and fusiform but ap- 

 parently no branched cells. The iris and ciliary processes were 



I Lunette Encyclopedic on Dictionaire Raisonnfe, 1780. 

 a Smith's Optics. 



