Re: Heliochronometer by Homan

[Brooke Clarke]

Hi Andrew:

One thing you can do is read the patent images and look for citations of prior
art.
Sometimes this is on the first written page, sometimes on the last page and
sometimes in the description of prior art.
Once you have the patent number then go there and look for more citations.

I have some Sundial Patents at:
<http://www.pacificsites.com/~brooke/SD_Pat2.htm>

Have Fun,

Brooke

Andrew James wrote:

> Brooke
>
> Thank you for that - and thanks Fred for sending me the file off-list.
>
> >From that I now see that the US Patent 946,223 is actually for a design
> completely different from UK 18,568 of 1911 and the instrument I saw!
>
> As I understand that he made at least two other known mean time dials on yet
> another principle, Homan would seem to have been quite a prolific inventor
> in the field.
>
> Perhaps he took out other US Patents? But as you say apparently one can't
> search for the inventor on-line at that date. I'll have a look, in case, for
> other UK ones using good old paper-based technology!
>
> Andrew James
> N 51 04' W 01 18'
>
> -Original Message-
> From: Brooke Clarke [mailto:[EMAIL PROTECTED]
> Sent: 31 July 2002 17:03
> To: sundial@rrz.uni-koeln.de
> Subject: Re: Heliochronometer by Homan
>
> All US patents are on line.
> Sources for free on line TIF viewers can be found under help\How to Access
> Patent Full-page Images.
> Older patents can only be accessed by traditional US class number or patent
> number, none of the other search methods will work.
> -

-

RE: Heliochronometer by Homan

[Andrew James]

Brooke

Thank you for that - and thanks Fred for sending me the file off-list. 

>From that I now see that the US Patent 946,223 is actually for a design
completely different from UK 18,568 of 1911 and the instrument I saw!

As I understand that he made at least two other known mean time dials on yet
another principle, Homan would seem to have been quite a prolific inventor
in the field.

Perhaps he took out other US Patents? But as you say apparently one can't
search for the inventor on-line at that date. I'll have a look, in case, for
other UK ones using good old paper-based technology!

Andrew James
N 51 04' W 01 18' 

-Original Message-
From: Brooke Clarke [mailto:[EMAIL PROTECTED]
Sent: 31 July 2002 17:03
To: sundial@rrz.uni-koeln.de
Subject: Re: Heliochronometer by Homan

All US patents are on line.
Sources for free on line TIF viewers can be found under help\How to Access
Patent Full-page Images.
Older patents can only be accessed by traditional US class number or patent
number, none of the other search methods will work.
-

Re: Heliochronometer by Homan

[Brooke Clarke]

Hi:

All US patents are on line.
Sources for free on line TIF viewers can be found under help\How to Access
Patent Full-page Images.
Older patents can only be accessed by traditinal US class number or patent
number, none of the other search methods will work.
US 946,223 can be seen at:


Have Fun,

Brooke Clarke
PS the "<... >" should keep the link from breaking

fwsawyer wrote:

> The Homan sundial was also patented in the U.S.: Patent # 946,223 issued on
> 11 Jan. 1910.  I have a copy of the patent papers in a 320Kb pdf file which
> I will send to anyone who requests it (off-list please).
>
> Fred Sawyer
>
> - Original Message -
> From: "Andrew James" <[EMAIL PROTECTED]>
> To: 
> Sent: Wednesday, July 31, 2002 7:33 AM
> Subject: Heliochronometer by Homan
>
> > I have recently been shown an interesting brass heliochronometer made by
> W.
> > Homan of Glasgow according to his patent 18,568 of 1911. (I hope to
> receive
> > a copy of the patent shortly.)
> >
> > It is quite large, based on a 13 1/2" diameter hemisphere. It has two
> > "gnomons", upright brackets carried on and perpendicular to a circular
> plate
> > 11" diameter. The plate has, over an adjustable 15 degree arc at its edge,
> a
> > scale divided in minutes, and can be rotated by hand against an outer
> fixed
> > ring marked with hours from 1 to 12 twice. Each upright carries a half
> > analemma, one for positive and the other for negative solar declination
> > (summer and winter), and a slit - with in one case a small hole adding a
> > nodus to the slit - to project light onto the half analemma on the other
> > upright 7 7/8" (200 mm) away.
> >
> > It is set for a latitude (not adjustable) of about 7 degrees North, and a
> > time difference from the local meridian of 5 minutes (added to the
> reading,
> > so it was sited just over 1 degree West). This indicates it was made for
> use
> > not in Britain but somewhere tropical, perhaps West Africa or Ceylon.
> >
> > Has anyone come across other example(s), or information about this device
> or
> > its maker?
> >
> > Andrew James
> > N 51 04' W 01 18'
> > -
> >
>
> -

-

Re: Heliochronometer by Homan

[fwsawyer]

The Homan sundial was also patented in the U.S.: Patent # 946,223 issued on
11 Jan. 1910.  I have a copy of the patent papers in a 320Kb pdf file which
I will send to anyone who requests it (off-list please).

Fred Sawyer

- Original Message -
From: "Andrew James" <[EMAIL PROTECTED]>
To: 
Sent: Wednesday, July 31, 2002 7:33 AM
Subject: Heliochronometer by Homan


> I have recently been shown an interesting brass heliochronometer made by
W.
> Homan of Glasgow according to his patent 18,568 of 1911. (I hope to
receive
> a copy of the patent shortly.)
>
> It is quite large, based on a 13 1/2" diameter hemisphere. It has two
> "gnomons", upright brackets carried on and perpendicular to a circular
plate
> 11" diameter. The plate has, over an adjustable 15 degree arc at its edge,
a
> scale divided in minutes, and can be rotated by hand against an outer
fixed
> ring marked with hours from 1 to 12 twice. Each upright carries a half
> analemma, one for positive and the other for negative solar declination
> (summer and winter), and a slit - with in one case a small hole adding a
> nodus to the slit - to project light onto the half analemma on the other
> upright 7 7/8" (200 mm) away.
>
> It is set for a latitude (not adjustable) of about 7 degrees North, and a
> time difference from the local meridian of 5 minutes (added to the
reading,
> so it was sited just over 1 degree West). This indicates it was made for
use
> not in Britain but somewhere tropical, perhaps West Africa or Ceylon.
>
> Has anyone come across other example(s), or information about this device
or
> its maker?
>
> Andrew James
> N 51 04' W 01 18'
> -
>

-

Re: Heliochronometer by Homan

[Peter Tandy]

Dear Andrew,

have a look at the most recent 'Sundial Page' in Clocks magazine (written
by Chris Daniel of the BSS), which deals with these instruments made by
Homan. He too has just found an exaple, and would like to know of other
examples.
regards

peter tandy



At 12:33 PM 7/31/02 +0100, you wrote:
>I have recently been shown an interesting brass heliochronometer made by W.
>Homan of Glasgow according to his patent 18,568 of 1911. (I hope to receive
>a copy of the patent shortly.)
>
>It is quite large, based on a 13 1/2" diameter hemisphere. It has two
>"gnomons", upright brackets carried on and perpendicular to a circular plate
>11" diameter. The plate has, over an adjustable 15 degree arc at its edge, a
>scale divided in minutes, and can be rotated by hand against an outer fixed
>ring marked with hours from 1 to 12 twice. Each upright carries a half
>analemma, one for positive and the other for negative solar declination
>(summer and winter), and a slit - with in one case a small hole adding a
>nodus to the slit - to project light onto the half analemma on the other
>upright 7 7/8" (200 mm) away. 
>
>It is set for a latitude (not adjustable) of about 7 degrees North, and a
>time difference from the local meridian of 5 minutes (added to the reading,
>so it was sited just over 1 degree West). This indicates it was made for use
>not in Britain but somewhere tropical, perhaps West Africa or Ceylon.
>
>Has anyone come across other example(s), or information about this device or
>its maker? 
>
>Andrew James
>N 51 04' W 01 18' 
>-
>
>

-