But he's making an exception for the Penn Museum, an archaeology and anthropology centre that offers touch tours for the blind and visually impaired. Ayala can now feel the eroded limestone of an ancient Egyptian sarcophagus and the intricate hieroglyphs on the statue of a pharaoh.
"When I touch things, it's my version of a sighted person's eyes. It tells me way more than a person describing it would ever," Ayala said.
The institution, which is part of the University of Pennsylvania in Philadelphia, began offering the tours last year in an effort to make their extensive collections more accessible. Museums should serve the community at large, and that includes the unsighted as well as the sighted, said program co-ordinator Trish Maunder.
"Just because a person has low vision or can't see, doesn't mean that they're not completely interested in culture or learning about ancient artifacts," Maunder said.
Most major U.S. metro areas have at least one museum that offers some type of hands-on experience, from touching objects with bare hands or gloves to feeling replicas, according to Art Beyond Sight, a group that makes visual culture accessible to the blind and visually impaired.
Such accommodations began well before the Americans with Disabilities Act and have increased as museums "have transformed from institutions that house objects to institutions that work with audiences," said Nina Levent, executive director of the New York-based art organization.
Museums that don't offer tactile tours often have personal or audio guides for the blind. But Levent contends that developing touch components can benefit a wide range of visitors, including children's groups and students with learning disabilities.
"I'd be hard-pressed to think of an audience that does not want to touch," Levent said.
The Penn Museum has held hands-on tours twice each Monday — when the building is otherwise closed — for the past two fall seasons.
Ayala's recent visit came during a field trip with about a dozen classmates from the Overbrook School for the Blind. The students got to feel a quartzite likeness of Ramesses II, a black basalt statue of the goddess Sakhmet and two stone coffins. Smaller reproductions of the pharaoh and deity were available for those not tall enough to touch the tops of the statues.
Students sanitized their hands before feeling the pieces, which were pre-selected by conservators. Though thousands of years old, the artifacts shouldn't be damaged by clean fingers and a light touch, Maunder said.
The free tours include a classroom lesson on how Egyptians prepared a body for burial. Students jiggled a gelatin mould of the brain — which is removed during the mummification process — and handled facsimiles of relics found in tombs. They also felt ancient linen, smelled scented oils and touched a reproduction of a mummy.
Overall, the museum is engaging with nearly 250 blind or visually impaired people this fall, up about 32 per cent from last year, Maunder said. Educators are already planning next season's curriculum on ancient Rome.
The response from participants has been encouraging, said docent Austin Seraphin, who is also blind and helped develop the tour.
"Everyone seems really happy," Seraphin said. "We asked them to fill out surveys and reportedly we've been getting universally positive reaction. The one complaint we get is that students wish it were longer."
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