Improved Method of Bleaching Straw Hats

Join Our Community of Science Lovers!


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


This method is described as far surpassing, in efficiency and beauty of result, any other known process. The soap is brushed off clean with a delicate brush. The hats, while yet wet, are immersed in a bath, prepared of three-fourths of an ounce of sulphite of hydro-sulphite of soda, and four to six pounds of water, and are freely handled and pressed, to promote the soaking in of the lye through the interstices of the plaits. No harm is to be apprehended from this manipulation, as the previous washing has rendered the straw pliable, and without danger of fracture. The hats are then removed from the lye, and three-fourths of an ounce of muriatic acid of commerce being added and well stirred into this lye, the hats are quickly replunged in it. To secure a uniform action of the acid upon the lye which is in the hats, particular care must be taken that the hats be submerged at once, and kept in this situation. In order to prevent the escape of the liberated sulphurous acid gas, the vessel employed is, after the second immersion kept closed, until the operation be completed ; this takee place in about thirty minutes, more or less, according to the darkness of the straws. When sufficiently acted on by the gas, the hats are removed, washed clean in pure water, dried, and finished as usual.

Scientific American Magazine Vol 13 Issue 12This article was published with the title “Improved Method of Bleaching Straw Hats” in Scientific American Magazine Vol. 13 No. 12 (), p. 94
doi:10.1038/scientificamerican11281857-94b

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe