HE AIN’T HEAVY … Five large-scale graphite drawings by Robyn O’Neil are on display through this weekend in “My brother holds tight my feeble hand.” Through Saturday, 11 a.m.-6 p.m., Clementine Gallery, 526 W. 26th St., between Tenth and Eleventh avenues, second floor, 212-243-5937, free.

STRAIGHT LINES The exhibit “3 x Abstraction,” which closes Saturday, features geometric abstract drawings by three women of different generations. Hilma af Klint (1862-1944), Emma Kunz (1892-1963), and Agnes Martin (1912-2004) used formalism as a way of exploring science and philosophy. Although Martin’s work is well-known, af Klint and Kunz have been largely overlooked. Kunz used a pendulum to plan the structure of her complex drawing, making each in its own continuous session. She was a healer and housekeeper who considered her drawings to be images of energy fields from which she would formulate diagnoses for her patients. Fifteen of her large-scale drawings are on display in the exhibit. Af Klint painted landscapes and portraits to earn her living, experimenting on her own time with “automatic drawings” and geometric compositions. Many of her works in the exhibit have never been seen in America. Through Saturday, today-Friday, 10 a.m.-6 p.m., Saturday, 11 a.m.-6 p.m., the Drawing Center, 35 Wooster St., between Broome and Grand streets, 212-219-2166, $3 suggested donation.

BUILDING BELIEF Photographs by Larry Racioppo, on view through Friday in “Architecture of Devotion,” depict local Roman Catholic sites of worship. The exhibit focuses on New York’s Italian-American community over the past 100 years. Through Friday, 10 a.m.-4 p.m., Italian American Museum, 28 W. 44th St., between Fifth and Sixth avenues, 17th floor, 212-642-2020, free.

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