{"id":3156,"date":"2018-07-12T09:51:54","date_gmt":"2018-06-28T18:16:04","guid":{"rendered":"http:\/\/commons.princeton.edu\/josephhenry\/student-notes\/"},"modified":"2018-07-12T09:51:54","modified_gmt":"2018-07-12T14:51:54","slug":"student-notes","status":"publish","type":"page","link":"https:\/\/commons.princeton.edu\/josephhenry\/student-notes\/","title":{"rendered":"Student Notes"},"content":{"rendered":"

Below is an excerpt from the notebook. Professor Henry explained first the non-astatic, and then the astatic galvanometer. He uses the terms “simple” and “compound” galvanometers for each, respectively.
\nsimple<\/p>\n

\"\"
Daniel Ayres’ sketch of simple galvanometer<\/figcaption><\/figure>\n

“There are two forms of the instrument [the galvanometer] called the simple and compound. The first replicated in Fig 1st consists of [a] large coil of wire ED rolled upon itself and insulated with silk or wax, in this a needle N is suspended by a silk thread BC from a movable head A. The two ends of the copper wire coil terminate in two cups PP\u2019 containing a little mercury in order that they may be united with the poles of a battery when a current is required to be tested, and the whole is covered with a glass case.”
\ncompound<\/p>\n

\n
\"\"
Daniel Ayres’ sketch of compound galvanometer<\/figcaption><\/figure>\n

“The compound galvanometer differs from the simple, only in having a greater number of needles. By this means we not only neutralize the magnetic influence of the earth, but also make the instrument more sensitive. These needles are suspended by a thread fastened to a straw ab or some other light substance into which the needles are placed.” -Daniel Ayres Jr.’s Student Notebook, lecture notes from Joseph Henry’s Natural Philosophy class, 1841<\/p>\n","protected":false},"excerpt":{"rendered":"

Below is an excerpt from the notebook. Professor Henry explained first the non-astatic, and then the astatic galvanometer. He uses the terms “simple” and “compound” galvanometers for each, respectively. simple “There are two forms of the instrument [the galvanometer] called the simple and compound. The first replicated in Fig 1st consists of [a] large coil … Continue reading “Student Notes”<\/span><\/a><\/p>\n","protected":false},"author":5,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"categories":[],"tags":[],"class_list":["post-3156","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/commons.princeton.edu\/josephhenry\/wp-json\/wp\/v2\/pages\/3156","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/commons.princeton.edu\/josephhenry\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/commons.princeton.edu\/josephhenry\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/commons.princeton.edu\/josephhenry\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/commons.princeton.edu\/josephhenry\/wp-json\/wp\/v2\/comments?post=3156"}],"version-history":[{"count":1,"href":"https:\/\/commons.princeton.edu\/josephhenry\/wp-json\/wp\/v2\/pages\/3156\/revisions"}],"predecessor-version":[{"id":3159,"href":"https:\/\/commons.princeton.edu\/josephhenry\/wp-json\/wp\/v2\/pages\/3156\/revisions\/3159"}],"wp:attachment":[{"href":"https:\/\/commons.princeton.edu\/josephhenry\/wp-json\/wp\/v2\/media?parent=3156"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/commons.princeton.edu\/josephhenry\/wp-json\/wp\/v2\/categories?post=3156"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/commons.princeton.edu\/josephhenry\/wp-json\/wp\/v2\/tags?post=3156"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}