Clavius, Christoph - Geometria practica

Scan	Original
31
32
33	3
34	4
35	5
36	6
37	7
38	8
39	9
40	10
41	11
42	12
43	13
44	14
45	15
46
47	17
48	18
49	19
50	20
51	21
52	22
53	23
54	24
55	25
56	26
57	27
58	28
59	29
60	30

344GEOMETR. PRACT.

INSTRVMENTI PARTIVM
Conſtructio, atque vſus.
CAPVT I.

FIant ex orichalco, vel alia materia ſolida duæ regulæ ABD,
11Inſtrumentũ
partium quo
pacto cõſtrua-
tur. AEC, æquales omnino, quæ in A, ita coniungantur clauo
aliquo tereti, vt circa A, vniformiter poſsint moueri, quem-
admodum in Norma vulgari, quæ, prout opus eſt, conſtrin-
gi poteſt, & dilatari, fieriſolet. Deinde ex A, in planis dicta-
rum regularum duæ rectæ ducantur AF, AG, eæquein 100. particulasæ-
quales diſtribuantur, velin 1000. ſi longiores ſint. Ita enim ex qualibet recta
quotuis partes centeſimæ, aut milleſimæ abſcindi poterunt. Immo ſi ſumatur
linea KL, continens 11. particulas ex illis 100. vel 1000. diuidaturq; in 10.
partesæquales, ſi quidem ſecta ſit vtraque regulain 100. partes æquales, po-
terunt beneficio rectæ KL, continentis 11. particulas eiuſmodi, & in 10. par-
tes æquales diuiſæ, ex data recta qualibet accipi quotuis milleſimæ partes,
perinde ac ſi partes ſingulæ centeſimæ in vtraque regula ſectæ eſſent in de-
nas particulas æquales: ſi vero vtraqueregula in 1000. particulas diſtributa
ſit, & linea KL, talium 11. partium in 10. particulas diſſecta, poterunt ex qua-
uis linea recta propoſita partes, quot quis voluerit, milleſimarum decimæ
auferri, non ſecus ac ſi ſingulæ partes milleſimæ in regula diſtributæ eſſent in
10. particulas æquales, vt in vſu inſtrumenti dicemus.

Rvrsvs ſiregula contineat 100. partes, & recta quæpiam MN, con-
ſtans ex 101. eiuſmodi particulis diſtribuatur in 100. partes, poterimus ex
quauis data recta accipere partes decimas milleſimarum. At ſi inregula no-
tatæ ſint 1000. partes, & linea quæpiam continens eiuſmo dipartes 101. ſece-
tur in 100. partes, deprehendipoterunt in qualibet recta quotcunque par-
tes centeſimæ milleſimarum, ac ſi partes ſingulæ milleſimæ in regula comple-
cterentur partes 100. Si denique linea earum partium 1001. diuidatur in
1000. partes, capiemus in quauis recta partes milleſimas milleſimarum, per-
inde ac ſi partes milleſimę ſingulæ in regula partes 1000. comprehende-
rent, vt ex vſu inſtrumenticonſtabit. Atque hæc eſt conſtructio inſtrumenti
in vna facie pro partibus linearum rectarum inquirendis.

In altera vero inſtrumenti facie deſignantur chordæ omnium arcuum
quadrantis hoc modo. Ductis ex centro A, rectis AF, AG, vt in priori fa-
cie, ſumendus eſt quadrans circuli chordam habens æqualem rectæ, AF, &
in rectas AF, AG, transferenda chorda gradus 1. illius quadrantis, deinde
chorda grad. 2. 3. 4. 5. & ſic deinceps vſque ad chordam 89. graduum: ita
enim ex quolibet quadrante abſcindere licebit arcum quotcunque gra-
duum, vt Num. 16. dicetur: quamuis nos beneficio particularum æ qualium
in priori facie poſitarũ capiemus ex quadrante propoſito non ſolum gradus
integros, ſed etiam minuta, quod Num. 14. docebimus. Atq; ita abſoluta eſt
conſtru ctio inſtrumenti in altera facie. Huius inſtrumenti vſus ampliſsimus
eſt, vt diximus, & non obſcurè exiis, quæ ſequuntur, intelligipoteſt.

Page concordance

Text layer

Text normalization

Search

Scan	Original
31
32
33	3
34	4
35	5
36	6
37	7
38	8
39	9
40	10
41	11
42	12
43	13
44	14
45	15
46
47	17
48	18
49	19
50	20
51	21
52	22
53	23
54	24
55	25
56	26
57	27
58	28
59	29
60	30

Scan	Original
31
32
33	3
34	4
35	5
36	6
37	7
38	8
39	9
40	10
41	11
42	12
43	13
44	14
45	15
46
47	17
48	18
49	19
50	20
51	21
52	22
53	23
54	24
55	25
56	26
57	27
58	28
59	29
60	30

Scan	Original
31
32
33	3
34	4
35	5
36	6
37	7
38	8
39	9
40	10
41	11
42	12
43	13
44	14
45	15
46
47	17
48	18
49	19
50	20
51	21
52	22
53	23
54	24
55	25
56	26
57	27
58	28
59	29
60	30