<p>These are the patent drawings for a device intended for amusement and exercise for babies and small children.  
The inventor was Helen Campbell of Yakima, Washington.
</p>
The 1924 U.S. patent for this device was applied for in 1922.  Its patent number is <a rel="nofollow" class="external text" href="http://patimg2.uspto.gov/.piw?Docid=01509750&amp;homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect1%3DPTO1%26Sect2%3DHITOFF%26d%3DPALL%26p%3D1%26u%3D%2Fnetahtml%2FPTO%2Fsrchnum.htm%26r%3D1%26f%3DG%26l%3D50%26s1%3D1,509,750.PN.%26OS%3DPN%2F1,509,750%26RS%3DPN%2F1,509,750&amp;PageNum=&amp;Rtype=&amp;SectionNum=&amp;idkey=NONE&amp;Input=View+first+page">1,509,750</a>.
Helen Campbell
1922
<p><a rel="nofollow" class="external text" href="http://patimg2.uspto.gov/.piw?Docid=01509750&amp;homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect1%3DPTO1%26Sect2%3DHITOFF%26d%3DPALL%26p%3D1%26u%3D%2Fnetahtml%2FPTO%2Fsrchnum.htm%26r%3D1%26f%3DG%26l%3D50%26s1%3D1,509,750.PN.%26OS%3DPN%2F1,509,750%26RS%3DPN%2F1,509,750&amp;PageNum=&amp;Rtype=&amp;SectionNum=&amp;idkey=NONE&amp;Input=View+first+page">Patent 1,509,750</a> of the U.S. Patent and Trademark Office <br></p>
If your computer doesn't display the drawings of the patent when you click that link (which goes to the page of that patent at the website of the U.S. Patent and Trademark Office), you need to <a rel="nofollow" class="external text" href="http://appft.uspto.gov/netahtml/PTO/help/images.html">install a plug-in</a> that will enable your web browser to display a TIFF file.  Using such a plug-in might increase your web browser's zoom level (its magnification level) to 200% at all webpages (until you reset it to 100%). You can avoid needing to install such a plug-in by going to a search engine such as Google and typing the patent's number (1,509,750) and the word "patent" in the keyword searchbox.  This will deliver links to the patent's page at non-governmental patent-search websites.  At most of those websites, the images' file format isn't TIFF.