The Whyte studios seem to have been careful over a long period to number their products, which offers the possibilty of sequencing and even approximately dating them. If as a first approximation it is assumed that the 'production rate' was reasonably constant over the period it would mean that the average of the numbers found on the cards from this address would have occurred near the middle of the period, leading to an estimate of the yearly rate of just over 7100. This rate (equivalent to just over 20/day) seems high, but Whyte would have had a number of assistants and even studios.
This first card above, supplied by George Mason & Co., is numbered 5491, which along with the design on the back, suggests a date in the first year or so of his operations at this address. Indeed Whyte is only recorded in West Kilbride in 1886, (Ref. 7) but could have been there a year earlier. The second cdv above is not numbered, (or has lost the number where it was trimmed at the bottom) but the 'two ships' design was used in the mid to late 1880s and perhaps the very early 1890s.
The two cdvs above are clearly marked 16788 and 20463, so we could approximate the dates to 1887 and 1888 respectively using our rough calculation.
If it is assumed that the number on the first cabinet card below is 20285, it would be dated between the two above, and mark the transition from one design to the other. The dark card below it is unfortunately not numbered, but is probably slightly later, as this form usually preceded the use of embossed lettering as seen in the two cdvs below it again. The cards with the 'swan' design on the back are thus reassuringly of the same period as those with the same design used by Edgar and Steven. (The graphic form of the name at the bottom left of these cabinet cards, however, is the same as that used on the cabinet cards below at a later date, with a different form apparently intervening).
The two cdvs below with the 'C,E & C' design on the back would on the same basis come from about 1888 and 1889 respectively. The first carries the printer's name - 'McGhie & Bolton' They show the same curtain, and two similarly attired ladies.