Re: The TRIRADIUS in a fingerprint: how it develops, it's characteristics + a definition!

**Martijn (admin)** Fri Apr 29, 2011 3:48 pm

Lynn wrote:
Patti wrote:I think this is the FBI's innermost diverging parallel ridges. The FBI describes 1 set and Schaumann & Alter mention 3 sets of diverging ridges. 3 sets may contain the Y or Star shape and 3 sets may appear as a triangular plot as per Cummins & Midlo.

yes i think he is talking about FBI's innermost diverging parallel ridges too. They may contain the star, or appear as a triangular plot, but they might also diverge with a white space in the centre between them, or a dot, or a short ridge (like c & d in fig 78)

No Patti & Lynn ... Wilder is definitely NOT talking about the F.B.I.'s 'type lines'!

Because the F.B.I. type lines are ALWAYS found outside the pattern area. And this implicates that Wilder's second aspect of how a delta can manifest ("the wide seperation of two ridges ") ... should for sure not be associated with the F.B.I.'s type lines: because the delta is ALWAYS found inside the pattern area.

PS. I think you both here assumed that Wilder is describing the 'delta' as a point.... but if you read his words carefully... then you will recognize that he is talking about the same type of delta that Galton had described!!! Which is not a single 'point'... !

**Lynn** Fri Apr 29, 2011 3:51 pm

Martijn (admin) wrote:

Lynn, that second variant relates to e.g. the 'island'-variant (Cummins & Midlo's figure 47E), and the empty variant (Cummins & Midlo's variant figure 47F).

Does this now makes sense for you as well?

Yes of course I recognised that immediately. (although C&M fig 47 F could be seen like Wilder's fig 78 e). I think the second variant also applies to the empty variant of Penrose 3.5 E

But that is not really important at all for our discussion...

on the contrary Martijn, I think it is VERY important for our discussion!

much more important is the following crucial element:

The word 'forking' is crucial... because in Henry's work it is directly associated with the delta as a 'three pointed star' (= the triradius!), and the same word 'forking' is included the in the F.B.I. definition of the word bifurcation... which implicates that the F.B.I.'s bifurcation can also be associated with the concept of... the tiradius!

Yes I agree with you that Henry's words confirm your point. But I think they also confim my point too, about my original understanding of what a triradius is (the 3 innermost diverging ridges from the 3 fields) - which surround the 'triradial area' in Penrose 3.5 E.
You have focussed on the bifurcation, but he is also giving an equally 'usual' example in the diverging ridges.

NOTICE: Even in Wilder's work the word 'delta' was still defined as a larger concept than a point (just like it was in Galton's work), because Henry writes:

"The deltas, as in the interpretation of a palm, are the first points to look for. These points give the appearance of triangles or often three pointed stars, but the careful study of the ridges composing them shows that they may be formed in a variety of ways."

(NOTICE: Wilder's use of the word 'points' could be a bit confusing... because his 'delta' is not a true single point...!!)[/color]

And thus, so far Cummins & Midlo is still the oldest work that we have discussed where the word 'delta' was re-defined as a single 'point'. Because also in Wilder's work that was not yet the case... and in that perspective we should be very aware of this to read his word properly!

Yes I am reading Wilder's 'delta' as 'triradius' rather than as 'triradial point'.

**Martijn (admin)** Fri Apr 29, 2011 3:57 pm

Patti wrote:Good! I see you now understand that all along there has been the idea of two kinds of triradii. A star shape (or your bifurcation like Y shape) and the delta shape, the triangle. Both equally acceptable for the location of the triradial point. Which is something I think Lynn agrees to as well.

And yes, you pointed out many times I was wrong!

Patti... at a much earlier phase I have described Penrose figure 4G as one of the 'true' example of a triradius. (And Lynn agreed with me about that point)

(Sorry, I don't see how your comment relates to what I described in the 2nd preceeding post before your comment above.)

**Lynn** Fri Apr 29, 2011 3:57 pm

Martijn (admin) wrote:PS. I think you both here assumed that Wilder is describing the 'delta' as a point....

No, I did not assume that.

**Martijn (admin)** Fri Apr 29, 2011 4:00 pm

Lynn wrote:
Martijn (admin) wrote:

Lynn, that second variant relates to e.g. the 'island'-variant (Cummins & Midlo's figure 47E), and the empty variant (Cummins & Midlo's variant figure 47F).

Does this now makes sense for you as well?

Yes of course I recognised that immediately. (although C&M fig 47 F could be seen like Wilder's fig 78 e). I think the second variant also applies to the empty variant of Penrose 3.5 E

Thanks for confirming... yes, and Schaumann & Alter's 3.5 E as well.

**Lynn** Fri Apr 29, 2011 4:01 pm

Martijn (admin) wrote:No Patti & Lynn ... Wilder is definitely NOT talking about the F.B.I.'s 'type lines'!

Because the F.B.I. type lines are ALWAYS found outside the pattern area. And this implicates that Wilder's second aspect of how a delta can manifest ("the wide seperation of two ridges ") ... should for sure not be associated with the F.B.I.'s type lines: because the delta is ALWAYS found inside the pattern area.

PS. I think you both here assumed that Wilder is describing the 'delta' as a point.... but if you read his words carefully... then you will recognize that he is talking about the same type of delta that Galton had described!!! Which is not a single 'point'... !

which ridges do you think he is talking about then Martijn?
re -

the delta is ALWAYS found inside the pattern area.

are you talkiing about FBI delta or scientific delta?

Patti Fri Apr 29, 2011 4:06 pm

Lynn wrote:
Martijn (admin) wrote:

(NOTICE: Wilder's use of the word 'points' could be a bit confusing... because his 'delta' is not a true single point...!!)

And thus, so far Cummins & Midlo is still the oldest work that we have discussed where the word 'delta' was re-defined as a single 'point'. Because also in Wilder's work that was not yet the case... and in that perspective we should be very aware of this to read his word properly!

Yes I am reading Wilder's 'delta' as 'triradius' rather than as 'triradial point'.

Wilder tells us the 'point' to find is in the center of the Star or Triangle - moved to the ridge for the triangle.

<edit> Top of page 194, "point of delta"

**Lynn** Fri Apr 29, 2011 4:25 pm

Patti wrote:
Lynn wrote:
Martijn (admin) wrote:

(NOTICE: Wilder's use of the word 'points' could be a bit confusing... because his 'delta' is not a true single point...!!)

And thus, so far Cummins & Midlo is still the oldest work that we have discussed where the word 'delta' was re-defined as a single 'point'. Because also in Wilder's work that was not yet the case... and in that perspective we should be very aware of this to read his word properly!

Yes I am reading Wilder's 'delta' as 'triradius' rather than as 'triradial point'.

Wilder tells us the 'point' to find is in the center of the Star or Triangle - moved to the ridge for the triangle.

<edit> Top of page 194, "point of delta"

thanks Patti.
Now it becomes confusing! on page 194 he also says....
"in all cases where the word delta is used the point of delta is intended."

**Martijn (admin)** Fri Apr 29, 2011 4:26 pm

Lynn wrote:
Martijn wrote:But that is not really important at all for our discussion...

on the contrary Martijn, I think it is VERY important for our discussion!

much more important is the following crucial element:

The word 'forking' is crucial... because in Henry's work it is directly associated with the delta as a 'three pointed star' (= the triradius!), and the same word 'forking' is included the in the F.B.I. definition of the word bifurcation... which implicates that the F.B.I.'s bifurcation can also be associated with the concept of... the tiradius!

(1) Yes I agree with you that Henry's words confirm your point.

(2) But I think they also confim my point too, about my original understanding of what a triradius is (the 3 innermost diverging ridges from the 3 fields) - which surround the 'triradial area' in Penrose 3.5 E.
You have focussed on the bifurcation, but he is also giving an equally 'usual' example in the diverging ridges.

NOTICE: Even in Wilder's work the word 'delta' was still defined as a larger concept than a point (just like it was in Galton's work), because Henry writes:

"The deltas, as in the interpretation of a palm, are the first points to look for. These points give the appearance of triangles or often three pointed stars, but the careful study of the ridges composing them shows that they may be formed in a variety of ways."

(NOTICE: Wilder's use of the word 'points' could be a bit confusing... because his 'delta' is not a true single point...!!)[/color]

And thus, so far Cummins & Midlo is still the oldest work that we have discussed where the word 'delta' was re-defined as a single 'point'. Because also in Wilder's work that was not yet the case... and in that perspective we should be very aware of this to read his word properly!

(3) Yes I am reading Wilder's 'delta' as 'triradius' rather than as 'triradial point'.

Thanks Lynn...

Ad 1) Great to hear that you now recognize as well how Henry's use of the word 'forking' in the perspective of his old use of the word 'delta' (and thus in the persective of the word triradius as well)... directly relates to the F.B.I.'s definition of the 'bifurcation'.

I hope you recognize as well how a 'triradius' be associated (in)directly with a 'forking'.

Ad 2) Lynn, earlier you described that your 'old' definition for a triradius was focussed on the complete 'triradial area'. But then we also agreed that many examples in Schaumann & Alter's figure 3.5 can not be described as 'triradii' (because the meeting of 3 ridges is missing in B, C, D and E).

So... thinking

... since Wilder is basically still using Galton's 'old' (outdated) concept for a delta (triadius), I don't recognize how his words could change your earlier conclusion.

For, I have described why I for sure can not agree with how Patti associated wilder's words with the F.B.I. definition of the type lines. Because I think Wilder is talking about 2 different variants which can not manifest combined... and therefore IF Wilder's first variant is present it will ALWAYS be featured with the F.B.I.'s type lines, but that can not implicate that Wilder's second variant is then also (ALWAYS) present, etc.

There really is a mistake behind Patti's association, and I am sure you should be find it as well if you read my former sentence carefully.

Ad 3) Great to know that we also agree about that.

Patti Fri Apr 29, 2011 4:26 pm

Lynn wrote:P.S. Patti, I'm not sure of the relevance of you posting fig 37, because there he is illustrating an extra-limital triradius on the palm, which isn't relevant to fingerprints. (?)

I uploaded that one because they have drawn all of the triradii as colored in triangles with radiants extended from the corners of the triangle. (as described by Cummins & Midlo for tracing radiants)

There are many others - Fig. 50, page 147 - there's a mix of triangles (not colored in) and ridges meeting as a star shape. Fig. 45 shows a sketch with the same types of triradii.

The TRIRADIUS in a fingerprint: how it develops, it's characteristics + a definition! - Page 9 Delta_14

The TRIRADIUS in a fingerprint: how it develops, it's characteristics + a definition! - Page 9 Delta_14

Which is the same as this to me. The yellow forms the triangular Delta shape and the green lines form the Star of 3 ridges radianting from the center or corners of the triangle.

**Martijn (admin)** Fri Apr 29, 2011 4:43 pm

Lynn wrote:
btw....Martijn, you said something about some of C&M work was outdated because it was older than the other sources,,,, but Henry's is even older than C&M ! and you embrace it ...because it agrees with what you were saying [/color]

Dear Lynn,

I have only 'embracced' the fact that Wilder EXPLICITELY uses the word 'forking' in the perspective of his delta concept.... but I am not embracing Wilder's work at all, because I actually think it is completely outdated! (And I expect that it sometimes will violate the F.B.I. rules, and possibly also the guidelines presented by later researchers).

For example: I have already pointed out that he is using Galton's outdated concept of a triradius. And in that perspective, one should be very ware of time when his work was written.

So, since we are living in the 21 century... I would not recocmmend it to use as a basic source, because while I admire my details in his work (including some fabulous illlustrations)... I also spotted quite a few 'confusing' elements on that page 193 that Patti shared with us.

A few more examples:

- His use of the word 'points' (3th alinea) is suggesting that he is talking about a delta-concept as a point; however that is not true at all. (But it is a rather old document, so for me there is no need to blame him of using a 'misleading' word-choice... but I would prefer to describe his work as outdated - for multiple reasons that I already described).

- His illustration in figure 78b is highly confusing, because his little circle can only be placed when more details about the location of the pattern area are known than what is seen in that example. And he does not explain it on page 193 either.

Lynn, I hope this makes sense in the perspective of my earlier comments today.

**Martijn (admin)** Fri Apr 29, 2011 4:52 pm

Lynn wrote:
Martijn (admin) wrote:No Patti & Lynn ... Wilder is definitely NOT talking about the F.B.I.'s 'type lines'!

Because the F.B.I. type lines are ALWAYS found outside the pattern area. And this implicates that Wilder's second aspect of how a delta can manifest ("the wide seperation of two ridges ") ... should for sure not be associated with the F.B.I.'s type lines: because the delta is ALWAYS found inside the pattern area.

PS. I think you both here assumed that Wilder is describing the 'delta' as a point.... but if you read his words carefully... then you will recognize that he is talking about the same type of delta that Galton had described!!! Which is not a single 'point'... !

(1) which ridges do you think he is talking about then Martijn?

re -
the delta is ALWAYS found inside the pattern area.

(2) are you talkiing about FBI delta or scientific delta?

Ad 1 - I already mentioned in an earlier response that the 2nd aspect Wilder is using as a typical manifestation shape for 'his delta' he is talking about ridges that are for example seen in Cummins & Midlo's figure 47 E (the ridges surrounding the dot) and F (the ridges surounding the central groove).

Ad 2 - I mentioned that Wilder using a likewise concept as Galton's delta! (see my PS comment)

Patti Fri Apr 29, 2011 4:58 pm

Martijn (admin) wrote:
Lynn wrote:
Martijn (admin) wrote:No Patti & Lynn ... Wilder is definitely NOT talking about the F.B.I.'s 'type lines'!

Because the F.B.I. type lines are ALWAYS found outside the pattern area. And this implicates that Wilder's second aspect of how a delta can manifest ("the wide seperation of two ridges ") ... should for sure not be associated with the F.B.I.'s type lines: because the delta is ALWAYS found inside the pattern area.

PS. I think you both here assumed that Wilder is describing the 'delta' as a point.... but if you read his words carefully... then you will recognize that he is talking about the same type of delta that Galton had described!!! Which is not a single 'point'... !

(1) which ridges do you think he is talking about then Martijn?

re -
the delta is ALWAYS found inside the pattern area.

(2) are you talkiing about FBI delta or scientific delta?

Ad 1 - I already mentioned in an earlier response that the 2nd aspect Wilder is using as a typical manifestation shape for 'his delta' he is talking about ridges that are for example seen in Cummins & Midlo's figure 47 E (the ridges surrounding the dot) and F (the ridges surounding the central groove).

Ad 2 - I mentioned that Wilder using a likewise concept as Galton's delta! (see my PS comment)

The ridges in Cummins & Midlo 47 E and F are basically the same as Penrose's G. In G the angles of the triangle are closed. In 47 E & F, the corners of the triangle are open.

In Kiwi's the Distal Angle is closed and the Marginal and Proximal Angles are open as one example. Shown here in the lower left corner.

The TRIRADIUS in a fingerprint: how it develops, it's characteristics + a definition! - Page 9 Delta_15

The TRIRADIUS in a fingerprint: how it develops, it's characteristics + a definition! - Page 9 Delta_15

**Martijn (admin)** Fri Apr 29, 2011 4:59 pm

Lynn wrote:
Martijn (admin) wrote:PS. I think you both here assumed that Wilder is describing the 'delta' as a point....

No, I did not assume that.

Yes, Lynn I understand. But I made that point there because it COULD have explained your agreement with Patti's comment. (Not sure about what Patti assumed while writing hercomment.. I think she hasn't responded to what I wrote.)

But it doesn't change anything about the reason why Patti's association should not be made (I have described it twice).

**Martijn (admin)** Fri Apr 29, 2011 5:18 pm

Patti wrote:
Martijn (admin) wrote:
Lynn wrote:
Martijn (admin) wrote:No Patti & Lynn ... Wilder is definitely NOT talking about the F.B.I.'s 'type lines'!

Because the F.B.I. type lines are ALWAYS found outside the pattern area. And this implicates that Wilder's second aspect of how a delta can manifest ("the wide seperation of two ridges ") ... should for sure not be associated with the F.B.I.'s type lines: because the delta is ALWAYS found inside the pattern area.

PS. I think you both here assumed that Wilder is describing the 'delta' as a point.... but if you read his words carefully... then you will recognize that he is talking about the same type of delta that Galton had described!!! Which is not a single 'point'... !

(1) which ridges do you think he is talking about then Martijn?

re -
the delta is ALWAYS found inside the pattern area.

(2) are you talkiing about FBI delta or scientific delta?

Ad 1 - I already mentioned in an earlier response that the 2nd aspect Wilder is using as a typical manifestation shape for 'his delta' he is talking about ridges that are for example seen in Cummins & Midlo's figure 47 E (the ridges surrounding the dot) and F (the ridges surounding the central groove).

Ad 2 - I mentioned that Wilder using a likewise concept as Galton's delta! (see my PS comment)

The ridges in Cummins & Midlo 47 E and F are basically the same as Penrose's G. In G the angles of the triangle are closed. In 47 E & F, the corners of the triangle are open.

In Kiwi's the Distal Angle is closed and the Marginal and Proximal Angles are open as one example. Shown here in the lower left corner.

Patti, in all examples that you just mentioned we are indeed talking about the 'triradial area'.... but that is also the the 'tiradial area' is also the point where the similaties end.

In Penrose's figure G there is for sure a (complete) triradius, but not in Schaumann & Alter's figure 47 E & F ... though these 2 examples do have a 'triradial point'!

Just like there is no true 'triradius' in Schaumann & Alter's figure 3.5 B and E.... but also in those examples there is a 'triradial point'!

Sorry Patti, regarding Kiwihands' fingerprint you are mixing the facts again with your phantasies:

Because if you focuss solely on the ridges... then you will see that there is no 'distal angle' at all, and your 'left corner' example is no TRIANGLE at all!!

Patti, I do understand how you made that 'lower left corner' example.... only you FORGET to add the upper ridge! And as a result it now looks like if there are two ridge that 'abut' ... but that result is a COMPLETELY MISLEADING representation of what is actually seen in Kiwihands' fingerprint:

Because so far I think we never disagreed that it does have a 'bifurcation'.

... Or are you suggesting with your 'lower left corner' example that in your perception there is no 'bifurcation' at all?

Patti Fri Apr 29, 2011 5:21 pm

Martijn (admin) wrote:
Lynn wrote:
Martijn (admin) wrote:PS. I think you both here assumed that Wilder is describing the 'delta' as a point....

No, I did not assume that.

Yes, Lynn I understand. But I made that point there because it COULD have explained your agreement with Patti's comment. (Not sure about what Patti assumed while writing hercomment.. I think she hasn't responded to what I wrote.)

But it doesn't change anything about the reason why Patti's association should not be made (I have described it twice).

I've responded to several things you've written.

Your letters in red warned us to read the text properly as you emphasized the triradial point was first mentioned by Cummins & Midlo and not in the work from Wilder and Wentworth. If you had only read the rest of the paragraph describing Fig. 78 Shocked

you would have seen for yourself they did describe the 'point of delta'.

Lynn pointed out to you that the Henry speaks of 2 configurations. The ridges meeting at a point in the center is the 3 pointed Star and the diverging ridges are an angle of the triangle. FBI's focus is primarily on the marginal angle, which you see as the main bifurcation.

The only issue with your argument is that it continues to give priority to one kind of configuration, the star. ALL sources describe the STAR and the DELTA.
Henry says "either" and "or".

Patti Fri Apr 29, 2011 5:24 pm

Martijn (admin) wrote:
Patti wrote:
Martijn (admin) wrote:
Lynn wrote:
Martijn (admin) wrote:No Patti & Lynn ... Wilder is definitely NOT talking about the F.B.I.'s 'type lines'!

Because the F.B.I. type lines are ALWAYS found outside the pattern area. And this implicates that Wilder's second aspect of how a delta can manifest ("the wide seperation of two ridges ") ... should for sure not be associated with the F.B.I.'s type lines: because the delta is ALWAYS found inside the pattern area.

PS. I think you both here assumed that Wilder is describing the 'delta' as a point.... but if you read his words carefully... then you will recognize that he is talking about the same type of delta that Galton had described!!! Which is not a single 'point'... !

(1) which ridges do you think he is talking about then Martijn?

re -
the delta is ALWAYS found inside the pattern area.

(2) are you talkiing about FBI delta or scientific delta?

Ad 1 - I already mentioned in an earlier response that the 2nd aspect Wilder is using as a typical manifestation shape for 'his delta' he is talking about ridges that are for example seen in Cummins & Midlo's figure 47 E (the ridges surrounding the dot) and F (the ridges surounding the central groove).

Ad 2 - I mentioned that Wilder using a likewise concept as Galton's delta! (see my PS comment)

The ridges in Cummins & Midlo 47 E and F are basically the same as Penrose's G. In G the angles of the triangle are closed. In 47 E & F, the corners of the triangle are open.

In Kiwi's the Distal Angle is closed and the Marginal and Proximal Angles are open as one example. Shown here in the lower left corner.

Patti, in all examples that you just mentioned we are indeed talking about the 'triradial area'.... but that is also the the 'tiradial area' is also the point where the similaties end.

In Penrose's figure G there is for sure a (complete) triradius, but not in Schaumann & Alter's figure 47 E & F ... though these 2 examples do have a 'triradial point'!

Just like there is no true 'triradius' in Schaumann & Alter's figure 3.5 B and E.... but also in those examples there is a 'triradial point'!

Sorry Patti, regarding Kiwihands' fingerprint you are mixing the facts again with your phantasies:

Because if you focuss solely on the ridges... then you will see that there is no 'distal angle' at all, and your 'left corner' example is no TRIANGLE at all!!

Patti, I do understand how you made that 'lower left corner' example.... only you FORGET to add the upper ridge! And as a result it now looks like if there are two ridge that 'abut' ... but that result is a COMPLETELY MISLEADING representation of what is actually seen in Kiwihands' fingerprint:

Because so far I think we never disagreed that it does have a 'bifurcation'.

... Or are you suggesting with your 'lower left corner' example that in your perception there is no 'bifurcation' at all?

You just don't get it.

**Martijn (admin)** Fri Apr 29, 2011 5:59 pm

Patti wrote:
You just don't get it.

Patti, you've managed to communicate your 'idea' very well.

But I can not accept it, because it includes an element of a phantasy: illustrated by the representation of only 'two meeting ridges' in the left bottom example (in the picture below).

You are ignoring the fact that there is a 'bifurcation'.

'Simples!'

The TRIRADIUS in a fingerprint: how it develops, it's characteristics + a definition! - Page 9 Delta_15

**Lynn** Fri Apr 29, 2011 6:05 pm

But then we also agreed that many examples in Schaumann & Alter's figure 3.5 can not be described as 'triradii' (because the meeting of 3 ridges is missing in B, C, D and E).

If I agreed to that, it may have been under pressure! ;-)
just to pick up on the word 'meeting'. It depends how you define it. eg Does 'meeting' mean they have to touch?
(for example, I 'meet' my friends at a cafe, we 'converge' around a table, but we do not join together like siamese twins!).

As I see it, in those examples there are 3 ridge systems 'meeting', converging together. B has only a dot in the middle, E doesn't have anything, just white space, but still the 3 ridge systems are meeting around this white space.

Actually in those examples we can still say that the ridge systems 'meet' in the sense of the word' 'join', but it is the groove part of the ridge systems that 'join' rather than the ridges.

Patti Fri Apr 29, 2011 6:16 pm

Martijn (admin) wrote:
Patti wrote:
You just don't get it.

Patti, you've managed to communicate your 'idea' very well.

But I can not accept it, because it includes an element of a phantasy: illustrated by the representation of only 'two meeting ridges' in the left bottom example (in the picture below).

You are ignoring the fact that there is a 'bifurcation'.

'Simples!'

The bifurcation or Star is on the right.

In this illustration I am combining a lot of resource information.

Newer models designed for biometrics describe the formation of the triradius as the last group of ridges to form. The 3 fields close in on each other.

This closing in of 3 fields is shown by the yellow triangles.

As more pressure is applied and/or less space is available at the time that the developmental stage is where the 3 innermost ridges are located they may form as a triangle Delta shape, in yellow, or completely pressurized or narrowed down in space to a Star shape, in green.

Biometrics and other developmental sources describe a wave of development in ridges - waving toward the triradius. In reality it takes days or weeks for the volar pad to rise and deflate - but *imagine* this slow motion process speeded up. (as in one of the graphics you uploaded)

There is a time and place that this wave comes to an end at the triradial point and the ridges are no longer formed of 'individual units' (Wilder) but the units have merged into rows. These individual units are formed after the Merkel cells form hexagon shaped groups and then in a 'connect the dot' fashion, create the rows, or merged units.

These rows form perpendicular to the tension from the nail bed, distally and laterally as well as the interphalangeal crease proximal to the fingertip.

These tensions and the flow results in only two configurations or 'variants' of these two. The two are the Star and the Delta. A 3 pointed star or a triangle.

"Some" examples of a 3 pointed Star as incomplete are found in the column on the right and some examples of the triangular Delta is shown on the left.

The TRIRADIUS in a fingerprint: how it develops, it's characteristics + a definition! - Page 9 Delta_16

The TRIRADIUS in a fingerprint: how it develops, it's characteristics + a definition! - Page 9 Delta_16

Patti Fri Apr 29, 2011 6:25 pm

Lynn wrote:
But then we also agreed that many examples in Schaumann & Alter's figure 3.5 can not be described as 'triradii' (because the meeting of 3 ridges is missing in B, C, D and E).

If I agreed to that, it may have been under pressure! ;-)
just to pick up on the word 'meeting'. It depends how you define it. eg Does 'meeting' mean they have to touch?
(for example, I 'meet' my friends at a cafe, we 'converge' around a table, but we do not join together like siamese twins!).

(now have to clean up my keyboard and make fresh coffee!!)

**Martijn (admin)** Fri Apr 29, 2011 6:39 pm

Lynn wrote:
But then we also agreed that many examples in Schaumann & Alter's figure 3.5 can not be described as 'triradii' (because the meeting of 3 ridges is missing in B, C, D and E).

If I agreed to that, it may have been under pressure! ;-)
just to pick up on the word 'meeting'. It depends how you define it. eg Does 'meeting' mean they have to touch?
(for example, I 'meet' my friends at a cafe, we 'converge' around a table, but we do not join together like siamese twins!).

As I see it, in those examples there are 3 ridge systems 'meeting', converging together. B has only a dot in the middle, E doesn't have anything, just white space, but still the 3 ridge systems are meeting around this white space.

Actually in those examples we can still say that the ridge systems 'meet' in the sense of the word' 'join', but it is the groove part of the ridge systems that 'join' rather than the ridges.

Lynn, ... no need to feel pushed by my words. You better take the time you need before giving an agreement.

But maybe you remember how I presented in the first post of this discussion an ADVANCED definition for the triradius composed by three elements? I quote:

"A 'triradus' can be recognized by the presence of the following three elements:
- (a) a meeting of 3 individual 'ridge fields'; the meeting-point of the 3 ridges is the 'triradial point', and the 3 'radiants' starting from this point should make angles close to 120 degrees - and all angles should be higher than 90 degrees. [NOTICE: ridges manifest in a fingerprint as 'black lines'].
- (b) the confluence of 3 parallel 'ridge systems' [NOTICE: 'ridge system' = one ridge + the surrounding grooves];
- (c) it's location borders the 'three topographic zones' of the fingerprint [NOTICE: topographic areas include: (I) proximal area + (II) distal area + (III) pattern area]."

Well, Loesch's definition explicitely describes all three elements::

"The triradius is formed when (c) three fields of paralllel lines meet and (b) its centre has three radiant lines which lie approaximately at (a) 120 degrees to one another."

That is why I have described Loesch's definition as not only the most recent definition that we have (except Coppock's rather short definition of course but basically only relates to the first element in my definition).

Both my earlier definition & Loesch's definition describe why Schaumann & Alter's B, C, D and E ... can not be described as representing examples of a 'triradius'.

bounce

Pressure is probably building up for you again, maybe I hope that these DEFINITIONS will finally make 'your fence' collaps to the ground! ( Wink

) ... so that you can not jump on it again!

But as an alternative... maybe we can now simply agree about the confirming 'value' of Loesch's definition for my definition?

Very Happy

Patti Fri Apr 29, 2011 6:41 pm

Martijn (admin) wrote:
Lynn wrote:
But then we also agreed that many examples in Schaumann & Alter's figure 3.5 can not be described as 'triradii' (because the meeting of 3 ridges is missing in B, C, D and E).

If I agreed to that, it may have been under pressure! ;-)
just to pick up on the word 'meeting'. It depends how you define it. eg Does 'meeting' mean they have to touch?
(for example, I 'meet' my friends at a cafe, we 'converge' around a table, but we do not join together like siamese twins!).

As I see it, in those examples there are 3 ridge systems 'meeting', converging together. B has only a dot in the middle, E doesn't have anything, just white space, but still the 3 ridge systems are meeting around this white space.

Actually in those examples we can still say that the ridge systems 'meet' in the sense of the word' 'join', but it is the groove part of the ridge systems that 'join' rather than the ridges.

Lynn, ... no need to feel pushed by my words. You better take the time you need before giving an agreement.

How long does she need to take to "disagree"

rolling on the floor

(good thing there was no more coffee left to spill)

**Martijn (admin)** Fri Apr 29, 2011 6:48 pm

Patti wrote:
The bifurcation or Star is on the right.

... Sounds to me that you just called your 'star-triradius' a bifurcation. Or did I misunderstood your words? (Because this contradicts with e.g. your earlier statement that you thought I had found my own state, named: 'Bifurcation land' ... despite that I had to disagree, I enjoyed that comment very much Very Happy

)

Patti, it would be helpful if you explain this comment at this stage..
Because does this implicate that you now finally recognize as well that a 'triradius' can been recognized as an element that can be associated with 'bifurcations' (additionally of course, only the triradius requires to have certain specifications that relate to the angles, etc.).

Patti Fri Apr 29, 2011 6:58 pm

Martijn (admin) wrote:
Patti wrote:
The bifurcation or Star is on the right.

... Sounds to me that you just called your 'star-triradius' a bifurcation. Or did I misunderstood your words? (Because this contradicts with e.g. your earlier statement that you thought I had found my own state, named: 'Bifurcation land' ... despite that I had to disagree, I enjoyed that comment very much )

Patti, it would be helpful if you explain this comment at this stage..
Because does this implicate that you now finally recognize as well that a 'triradius' can been recognized as an element that can be associated with 'bifurcations' (additionally of course, only the triradius requires to have certain specifications that relate to the angles, etc.).

Hahaha!
I did that for you so you'd understand the Star pattern is the 3 ridges meeting.

Actually after reading quotes from Wilder (earlier pdf Lynn shared) suggesting that forking ridges are just as much the meeting of two ridges rather than a splitting of one, I'm more inclined to understand why they use the term bifurcation when only two ridges meet at an angle.

This concept of ridges meeting rather than splitting works better with the concept of development and the rows forming due to perpendicular tension.

So the decision between a bifurcation and 3 ridges meeting at 120 degrees is as you pointed out the distance between the branches.

Two ridges running parallel and running/leaning into each other become conjoined.

In the triradial area the meeting of these 3 ridges should be based on a ridge from 3 fields and not ridges from 2 fields meeting.

A bifurcation is typically two ridges meeting or splitting. I think the degree apart is important.

I'm now ok with calling the Star a bifurcation. I do think it's misleading to do so.

Sponsored content