"With regard to the quantity of hops which the brewers in Scotland use for each quarter of malt, it is impossible to fix any certain data, as it varies from four to eight pounds, according to the quality of the ale, and the season of the year. In winter-brewings, six pounds of hops for the best ale, and four for the inferior kinds, may be considered a fair estimate."
"Scottish Ale Brewer", W.H. Roberts, 1847, page 89.
These hop rates are on the low side, but not exceptionally so. Whitbread's X Ales of this period had between 6 and 9 pounds of hops per quarter. Barclay Perkins X Ales, between 7 and 10 pounds per quarter. William Younger between 4 and 9 pounds per quarter in its shilling Ales.
"Our practice in brewing, from January to March, was, to allow ten pounds of hops per quarter of malt, when the wort was from 95 to 100 of specific gravity. Four pounds of the hops were put into the copper when the wort was about 200° of heat, and boiled briskly for the space of twenty minutes; the remaining six pounds were then added, and allowed to boil thirty or forty minutes, according to circumstances. If the gravity of the wort was from 85 to 90, we only made use of eight instead of ten pounds of hops per quarter, boiling four pounds for fifteen minutes, and the remaining four pounds from forty to fifty minutes, as mentioned above. But if the gravity of the wort was only from 70 to 80, seven pounds a quarter only were employed. Two pounds of these were boiled for twenty minutes, and the remaining five pounds put in and boiled for forty or fifty minutes, as before."That's nice and clear. Two hop additions, about half from the start of the boil, another 30 or 40 minutes before the end of the boil. That's a much larger late addition than in the English texts.
"Scottish Ale Brewer", W.H. Roberts, 1847, pages 89-90.
That's a new one. Leaving the hops from the first copper in the hop back and running the second wort over them. Or is that what they call a hop sparge?
To obtain, however, the remaining properties, as well as the malt extract that the former hops still retain, they either infuse them in hot liquor, which infusion they add to the second ale wort in the copper, or they allow the hops to remain in the hop-back, and run the second ale wort over them from the copper when boiled.
This practice is not so expensive as at first sight it may appear, because not only has the malt extract absorbed by the hops been obtained, but, as much of the remaining valuable parts of the hops have also been extracted, a smaller portion of these is necessary for the second boiling."
"Scottish Ale Brewer", W.H. Roberts, 1847, pages 89-91.
For Small Beer or Table Beer, the hops were re-used. Interesting taht he says this wasn't sytandard practice in Scotland. It's certainly what London brewers often did. And William Younger re-used hops in their weaker Stouts. Neither are two hop additions standard practice. At least according to Roberts. You'll have to decide if you can trust his word or not.
It will be observed, that the quantity of hops we made use of exceeds the proportion generally allowed by Scottish brewers, and that, in the three examples given, no portion of the hops was put into the copper until the wort was within a few degrees of the boiling point; and until this portion had boiled for twenty minutes, the remainder was not added. The result was, that we obtained for the finer ales the more delicate flavour of the hops, while much of the unctuous quality was still left to be imparted to the inferior ales or beers. Neither this, nor reboiling the hops, is the general practice; for many brewers put in the whole of the hops at the time when the wort is pumped into the copper."
"Scottish Ale Brewer", W.H. Roberts, 1847, pages 91-92.
That might be it for hop additions. But, seeing as no-one has screamed at me to stop yet, I might continue.