The beer’s specs: high CO2 content and low gravity, certainly sound like Berliner Weisse.
Weissbier has a high CO2 and low alcohol content, is a particularly refreshing drink, especially in the summer, and has an OG of 7-8% Balling.
To brew it half barley, half wheat-malt are used which makes it tingly, refreshing, and extremely palatable; But can also be made using with rice flour or broken rice up to 20% (and more), but it must first be gelatinised or the decoction method used; however, the infusion method is generally used.
Hops. These are not boiled directly with the wort, but are first boiled and this hop water is used to produce a mild taste. Aromatization. In order to obtain the well-liked flavour, spices are boiled in small sacks shortly before the wort is run off from the copper: citrus or cinnamon peels, cloves, coriander, juniper berries (the latter stir up the wild yeasts and bacteria) or they are added to the barrel when it is filled.
In order to facilitate "settling" in the cooler, vegetable finings (Irish moss) are already added in the copper and the wort is boiled until it breaks. As real finings 2 to 3 gr. of isinglass per hectolitre are added.
Attenuation: 50, or also up to 45%.
Some brewers, to help further clarification, pass the beer through a filter. - Before racking the Weissbier, which has been lagered for longer than 13 weeks (at 4-6° R [5º - 7.5º C]), has 0.5 to 1 liter of Kräusen per hectolitre added to it.
The yeast sits firmly on the bottom.
The clarified beer must have a fiery glow and foam in the glass.”
"Die Fabrikation obergäriger Biere in Praxis und Theorie" by Braumeister Grenell, 1907, pages 66 - 67. (My translation.)
Boiling the hops separately in water I’m sure I’ve heard of before. Not sure in what context. It sounds like another way of avoiding boiling the wort, which later in the 20th century was the case for Berliner Weisse.
The sacks of spices don’t sound very Reinheitsgebot. Nor Berliner Weisse. This book was published at a very odd moment: just about when the Reinheitsgebot was being introduced to the whole of Germany. The author describes several practices which I’m sure became illegal. It’s an interesting collection of spices. Orange peel and coriander sound like a Belgian Witbier. Though that’s probably no coincidence. Witbier is at the western end of a wheat beer tradition that stretched right across North Germany to Berlin.
Interesting that both Irish moss, isinglass and a filter were used. Sounds like they wanted to get a sparkling clear beer.
The section on Weissbier ends with some analyses:
|Analyses of Weissbier|
|Berln. Weisse I||3.91||4.85||0.17||0.32|
|„ „ II||3.33||4.28||0.16||0.2|
|„ „ Export||2.2||6.14||0.18||0.4|
|„ „ Jost||2.6||2.6||0.17||0.5|