Q. Why is it so hard to find a spot to go lap swimming (for those of us still inspired by the Olympics) year-round? There are so few pools to choose from, and most are so expensive. And the summer crowds at public pools are madness.

A. I wish I had a better answer, one that went beyond nodding my head in agreement, but the facts are these: Space is at a premium in New York City, and this extends to aquatic activities. For example, pool attendance at McCarren Park in Brooklyn increased by more than 20,000 people last summer from the previous summer. But there is one option for summertime lap swimmers: sign up for free early bird (7 a.m.) or night owl (7 p.m.) swims at your local city pool. Registration is simple, and you can be notified by email right away once you’ve been accepted to the program. If you’re looking for a one-time dip, Y.M.C.A.s around New York offer a free day pass.

Q. To escape the heat today, you can always sneak into a place that has the air-conditioning on full blast. But what did New Yorkers do before A.C. was invented?

A. In heat waves of old, New Yorkers rubbed their palms with ice chips, dangled their feet from fire escapes, and sometimes, higher numbers of police were deployed to keep watch over the public parks, where many New Yorkers chose to sleep in hopes of catching a breeze. But besides seeking shade and avoiding strenuous work, there was little respite from the heat.

Mariam Touba, a reference librarian with the New-York Historical Society, consulted a book by Edward P. Kohn, “Hot Time in the Old Town: The Great Heat Wave of 1896 and the Making of Theodore Roosevelt,” for answers. She wrote in an email that the book frequently mentioned high ice prices, so it “isn’t always clear how ordinary folks used the ice to cool their bodies.” She added that many tenement dwellers slept on rooftops and fire escapes to escape the heat, resulting in many accidents.

And journalists couldn’t help offering advice. A report called “Keeping Cool: How to Do It,” published in The New York Times in 1865, recommended that readers practice “moderation in diet, moderation in exercise, moderation in all things.” And if that failed? “Go down to the sea!”

Once air-conditioning kicked in, New Yorkers tried cooling methods that still exist today: They relaxed in movie theaters — air conditioning began to be installed in some of them in the 1920s — and soon sought out the chill of department stores.