Eakins and some great Philly painters he influenced are together in a PAFA-gang show

The oil sketch originated in 16th-century Italy as a preparatory study for a painting and gradually acquired its own distinct stature. To contemporary eyes, these sketches are often more appealing than a finished work. Typically deft and fluid, their brushwork doesn't aim for perfection. Thomas Eakins was a master of the form, and a fan.

Introduced to the practice during his four years of study in Europe, he made oil sketches an integral part of his own artistic output, and he used them as a teaching tool in his classes at the Pennsylvania Academy of the Fine Arts. Spontaneous, painterly oil sketching continues to inform the works of PAFA graduates — whether they follow his habit of seizing the moment in a sketch or take a slower approach to a subject.

"The Loaded Brush: The Oil Sketch and the Philadelphia School of Painting," now at PAFA, showcases works by 20 Philadelphia artists who have studied or taught at the school (or both) between the 1800s and today — including several sketches by Eakins. It was organized by Philadelphia painter and PAFA alum Patrick Connors.

Not surprisingly, Eakins' influence is strongest in his students' sketches. Thomas Anshutz's sketch of a female torso (from a plaster cast) and Susan Macdowell Eakins' Sketch of a Woman, both from the 1890s, were clearly rendered on the spot; they're dark in mood but free of any agonizing. (Macdowell didn't merely learn from Eakins. She married him.)  Several sketches by Cecilia Beaux also display that directness, including her charmingly odd Study for Harold and Mildred Colton, from 1886. Beaux attended PAFA while Eakins was there and admired his paintings, but she avoided studying with him. "A curious instinct of self-preservation kept me outside the magic circle," she later wrote.

Eakins was forced to resign from PAFA in 1886 after he scandalously removed a loincloth from a male figure model in class as female students looked on. Arthur B. Carles, who studied under Anshutz and Beaux at PAFA between 1900 and 1907, is the only artist in this show represented by a sketch and its "finished" version. Study for Helen Taylor, painted circa 1931, is a colorful but thinly painted outline of Taylor, while Helen Taylor, from the same year, is a completely realized work, except for Taylor's facial features, rendered vague and pale, as though an afterthought. You wonder whether Carles originally intended a more modern painting using color and line in the style of Matisse, as his study suggests. Eakins' direct aesthetic influences are nowhere to be seen.

But they're back in an undated painting by Louis B. Sloan of a leafless tree against a vivid sunset, with its thinly painted and actively worked surface, and in a plein-air painting of a distant Delaware River industrial scene by Stuart Shils. Sloan studied at PAFA in the 1950s and taught there for more than three decades. Shils is a PAFA graduate and current faculty member.

Both Elizabeth Osborne (former PAFA student and teacher) and Bill Scott (PAFA grad and current teacher) paint with an ecstasy and freedom that seems antithetical to Eakins' aesthetic, but the oil sketch's blithe spirit is alive and well in their work.

"The Loaded Brush" also features paintings by Brian Boutwell, Faye Swengel Badura, Stanley Bielen, Patrick Connors, Arthur DeCosta, Vincent Desiderio, Renée Foulks, Ben Kamihira, Peter Lister, Violet Oakley, Seymour Remenick, and Alice Barber Stephens.

Through Feb. 4 at the Pennsylvania Academy of the Fine Arts Hamilton Building, 118-128 N. Broad St., 10 a.m. to 5 p.m. Tuesdays through Fridays, 11 a.m. to 5 p.m. Saturdays and Sundays. Tickets: $15; $12 seniors and students. Information: 215-972-7600 or pafa.org.

The title of Tim Schwartz's first solo show with Larry Becker Contemporary Art, "Thin Air," is apt for his thinly painted monochromatic paintings.

Schwartz's 18 paintings from 2016 and 2017, shown here in two separate rooms, are effectively three related bodies of work loosely based on Buddhist prayer flags and the practice of meditation.

The oil-on-linen paintings that occupy the front of the gallery investigate densities of blue, green, red, and yellow, with three paintings executed in each color. Each painting's color is more thinly applied, in horizontal strokes, than the painting before it. Blue represents sky and space, green is water,  red is fire, and yellow is earth. They make the most articulate expression here of a particular dedication, possibly because there are more of them than paintings from the two other series.

In the back room, three works in graphite on linen — one huge, one medium-size, one tiny — suggest the process of meditation, while three predominantly white paintings seem to be a nod to Robert Ryman. Separating these colorless works from Schwartz's color-forward works in the front room makes good sense, but I suspect most people will respond more strongly to his investigations of color.

Through Dec. 30 at Larry Becker Contemporary Art, 43 N. Second St., 11 a.m. to 5 p.m. Fridays and Saturdays and by appointment. Information: 215-925-5389 or artnet.com/galleries/larry-becker-contemporary-art.

Having seen a few artists' installations at Glen Foerd, a wonderfully preserved 19^th-century Italianate mansion in Northeast Philadelphia, I'm always interested to see how artists will muse on the historic estate and house in their own work.

Talia Greene has done site-specific installations at the Morris-Jumel Mansion in New York's Washington Heights, among other history-laden places. Here, she addresses the social ambitions of Gilded Age grandees by covering the walls of a small room with a gilded wallpaper pattern that peels off to reveal a texture of mud, alluding to poorer living accommodations of the era.

Green's installation also includes her ironic cut-paper silhouettes of the entitled types who inhabited such mansions. Her transformation of the room is so subtly accomplished you may not notice it. I think that's her point.

Through July 2018 at Glen Foerd on the Delaware, Grant Avenue and Milnor Street; tours at 11 a.m. and 12:30 p.m. Fridays, Saturdays, and Sundays. Admission $5, children under 12 free. Admission to mansion's ground floor, where the installation is housed, is free on Saturdays from 1:30 to 3 p.m. Information: 215-632-5330 or www.glenfoerd.org.