Encyclopædia britannica : or, A dictionary of arts, sciences, and miscellaneous literature : constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises or systems .. . nfeaof greater magnifying powers are made : and they areapplied, by being fcrewed to the end A B, fig. »2. andthe brafs Aider N O is then taken away. The fame object may be varlouAy magnified, by thelenfes feverally applied to it ; and the degree of mag-nifying power is eafily known by this rule : j^s the ilif-tafice of the objeii is to that of its image from the magniJier ;
Encyclopædia britannica : or, A dictionary of arts, sciences, and miscellaneous literature : constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises or systems .. . nfeaof greater magnifying powers are made : and they areapplied, by being fcrewed to the end A B, fig. »2. andthe brafs Aider N O is then taken away. The fame object may be varlouAy magnified, by thelenfes feverally applied to it ; and the degree of mag-nifying power is eafily known by this rule : j^s the ilif-tafice of the objeii is to that of its image from the magniJier ; fo is the length or breadth of the objeii to that of theimiige. Inllead of the brafs Aiders with the lenfes NO,there is fometimes fcrewed a lens of a large fize, andlonger : the inilrument is then convertedinto a megalafcope s and is adapted for viewing the •larger kind of objeCls contained in large Aiders, fuchas is reprefented at R. And, in the fame manner-,iniall objects of entertainment, painted upon glafs likethe Aiders of a magic lanthorn, are much magnified,and reprefented upon the fame fcreen. The folar riilcrofcopes jufl defcribed are capable on-ly croftJ MICR o ? c orii \lnU ViC y/f/. ^/. ° / i ^S 9 g°S£^ A^.^.t/.) ivA/^,-/ht/.. ^ » MIC t 7 Ikrofcope Ijr of magnifying tranfparent ohjcdls ; for wliich piir-??< pofe tlic laft inllrument is extremely well ad;)iit as opaque ubicfts form the nioft conliderablc jiartof the curious collections in the works of art as wellas nature, a folar mierolcope for this purpofe was .ilong time wanted.—For feveral years previous to i 774,the late Mr Martin made feveral elTays towards theconftrution of fiKh an inrtrument ; and at lall com-pleted one about the time juli. mentioned, which henamed, III. The Opiqiie Solar Mkrofcope, With this in-flrument (to ufe his own words) all opaqve olijeMs,whether of the animal, vegstable, or mineral king-dtmi, may be exhibited in great perfctlion, in alltleirna
Size: 1346px × 1856px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorgleiggeorge1753, bookauthormacfarquharcolinca17451793
